RE: Small Block Chevy 400 Flywhe
I dont have a flywheel for you, but do have a couple suggestions that may help. You can use any small block Chevy flywheel. But, as you probably learned, the 400 flywheels have/need a balance plate. If you can pick up a used flywheel that will work for you and your budget, and isnt originally for a 400, you can buy a balance weight from J R Performance... I just bought one for my 400 (Im in the same situation as you)and here is the link for the plate: https://asp1.secure-shopping.com/jrmotorsportsltd/browse.asp?cat=1501005&path=1500000,1501000,1501005
With the shipping it is just over $20 for me, so might be a cheaper alternative for you all in all.
Also, I learned late that the 400 I have, which of course was set up for an automatic, didnt have the holes for the "pivot" the clutch linkage pivots on, so check that out. I am getting ready to drill and tap for mounting mine.
Hope that helps you some.
Tim