Recently bought a 73 Z with the original but tired L-82 350. I pulled the 350 to save it for future rebuild to return the car to original someday and installed a small block 400 in it's place. That is where the questions come in. 1. The SBC 400 runs very strong but vibrates hard as RPM increases. In the 67 Camaro with Turbo 350 trans the SBC 400 ran smoothly so am suspecting that it is not matched to the stock 11.5 inch clutch that came behind the 350 in the in the 73. I seem to remember something about SBC 400 being internally balanced/SBC 350 externally balanced. Am I right, and if so, what flywheel do I need to eliminate the vibration? 2. The temperature sender taps in the 202 heads on the SBC 400 are 1/2 inch, so the 3/4 inch senders from the 350 won't work. Which senders do I need to enable my temp gauge to work again? 3. We installed later model electronic ignition with the SBC 400 and have not attempted to reconnect the factory tach. Is it simply a matter of attaching the factory tach lead to the TACH terminal on the electronic ignition distributor cap or is other modification needed? Thanks in advance!