Buick V6 engines are a pain in the pisser. They changed the deck surface/cooling a few times. Head gaskets and heads have to be compatible with the block. Then one year they changed from odd fire to even fire and then a few months different they changed how the distributor drive and timing gear were installed. On one the distributor gear was machined on the front of the cam. On the other it bolted on. The cam has to match the crankshaft and that requires the matching timing set. A friend built a 3.8 for his 32 Ford. They could never get it to run right. He got a camshaft from a swap meet. I have a couple of books. One on just the Buick V6 and the other looks at a number of V6 engines. This is how they figured out the crankshaft/camshaft mismatch.
