This is my first post, never had much to contribute but I've been enjoying and learning a great deal from this website and the members here for quite some time. I've been able to save a lot of money and headaches just due to the info found on these forums. There's simply no other place like it on the net for this kind of info. Anyway, what motivated me to post was the subject of underbody primers, which I know has been discussed here many times. I have read quite a number of threads on the matter, so i hope I didn't miss any that might have already answered the questions I'm about to ask here. Several types of finishes have been discussed to emulate the Fisher Body primer sealer on the bottom of our cars. Although many have touted other brands, such a SPI and DuPont, the PPG epoxy primer (red oxide DP74LF) seems to have favor judging by mentions, plus it's the only one that folks feel proud enough about to actually post images of on their cars. Most of the guys who have used DP74 have had positive things to say about it's cosmetics and durability. It's worth mentioning that at least a few times I have read a post commenting that it's a little "too red" by a few guys, but I wonder if that depends on the year of the car, the lighting, or the weathering their car has endured, or the color of the overspray the bodies received during their final finish paint job. Were earlier cars coated with a more reddish primer? Some images posted here and elsewhere did seem to show DP74 that was quite red, while others looked spot on to me, especially judging by the photos of original survivor 1970 model year cars. In any case, I decided to use DP74LF on my car, which is a 1970. I plan to clear coat it to get just the right shine, using matted clears now on the market. First off, I cleaned the bottom of the car from front to back because it was coated in a rather thick filthy layer of old oil and road grime, most generated by an oil gauge line leak on the block that must have been going on for ages. It may have been a blessing, because I was surprised to learn that the oily layer (plus maybe the fact it's a California car) seems to have pretty much protected a very well preserved Norwood underbody red oxide primer for all these years. In fact, it looks nice enough that I'm still trying to decide if I need to do a full respray, or just fix a few places where it's worn off? What do you guys think I should do here? I also should mention I do have one small rust spot to repair. I an thinking that sadly, once I start spraying DP74LF I won't be able to stop until the whole floor is covered over since the new finish wont quite perfectly match the old worn finish, which also varies in color depth as you go back to the rear of the car. this is mainly due to a progressively heavier amount of body finish overspray coverage. On my car, which was white, this means it starts to make the primer look pink as you get closer to the trunk area. Well, getting to my main question. The DP74LF I got looks browner than I first expected when I opened the cans (I got two). It's not too red at all, in fact i had hoped it would be just a shade redder. So did they change the formula up? I did a brush out to compare to my car, and I guess it's good it's not any redder than it is. After a great deal of comparison, it's as close to a match for my 1970 as I think is possible to find, in fact even if I'd had it custom matched, I doubt i could get this close. Now my second question, I know once i spray this out it's not gonna look exactly the same as a brush out, but in my experience that should only affect the sheen and possibly the darkness level, and not the coloration in relation to red versus brown, am I right or wrong on this? I took some images to show you what I am talking about. Please comment if you have any observations or advice for me. Some images were taken in direct sunlight, others in deep shade, some in indirect light,. I tried not to use a flash, that always seems to make colors look off from what you would see under natural lighting. These are just shots of the underbody as it looks now. hard as hell to take good images of this area with only inches of room under the car. That's the original black firewall paint and the demark between it and the underbody paint. On my car, there's little to no overspray at the front of the car and along the sides, all that starts near the back sat bolt area and seems to have been caused mostly when they spray body color into the rear wheelwells. I see some restorers add it along the entire side of the car. Here's the two front drain plugs, are these just phosphated? They don't seem to rust. Obviously put in well after the base primer is put on. This area around the centerline transmission hump reinforcement had enough indirect sunlight hitting it that I was able to get what I consider a pretty good shot of some clean, non-faded factory primer in a true color. Most of the other photos I took, couched under the car, were either too dark or to fuzzy to see this amount of detail. This shows a view towards front from near the back, near the rear seat anchors. Here you can start to see the white overspray as it first shows up on the driveshaft tunnel. White paint on the left side was shot across from the left side of the car, and vice versa. This white overspray made the red oxide primer look pink or salmon tan. Here's the rear seat belt bolt anchor support end rubber bumper mount area for the rear end, the paint is nearly pink in color, lots of overspray from the wheelwell paint. MY car was never undercoated, but there was a small patch of some sort of factory undercoating or black sealer applied here around the support seams and on the bottom of the rear seat anchor area, I removed a great deal of it while i was cleaning, but it was a PITA to get off. I just wanted to make sure there was no rust under it, i think I will redo it, what do I use? Will rubber undercoating/truck bed liner spray last long? My dual mufflers also go here, will they catch rubber undercoating on fire, hehe?