The c5 is not as good a choice as the C4- it was used behind 4 and 6 cyls, so not quite as strong. The C4 will be your easiest and they're cheap to find/build. Maybe sell the 5 and use the $ for a 4. Or, if you're looking for highway gearing or mpg, why not go with an AOD and get the overdrive? I did in a 65 and love it! As far as the flywheel, the weaight is pertaining to the engine, not the trans- so use the one you have on the engine as long as the tooth count is correct. good luck
This isn't really true. First, a C5 can be turned into a C4 rather easily. I have done it twice. Second, for a stockish build, the C5 will operate just fine as is. Some think all C5s have a lock up converter, this is NOT true,but the majority do. So, if you want to run the C5 as is, you could. If you are interested in upgrading it to C4, it can also be done, but you need to spend some money on parts.