Help!! I have pulled and installed 6 or 7 170s with small bell housings in to/ out of falcons over the years. I never do a great job but they all seem to drive when I finish. But I recently picked up a nice 200 that was recently rebuilt. Sweet deal too. Here's my problem: I had a perfectly working C4. I bought a new torque converter and flex plate. I installed the converter, lined up the bolts on the flex plate, loosely bolted the bellhousing to the 2nd set of bolt holes on the block. Put the nuts on the converter. Everything lined up perfect. I was able to hand turn the engine and the converter turned with it. But when I started to tighten the trans to the block I could not turn over the engine. It felt like the center nub on the converter was pressing the center of the flex plate or the end of the crank (?) (in the center of the crank bolt holes). I put a few bolt rings on the back of the flex plate as spacers but when I tighten the trans to the block ...it would not turn. No change. I have been working on this for weeks and I am wits end. This a simple deal but I am obviously doing something really wrong. Any advice would be greatly appreciated.