Help with flexplate

Oh, so you have the correct crank bolt pattern, but you can't line up the last bolt for the converter???

Are you starting all of the bolts in the pattern before tightening them???

Sometimes it helps to keep it "loose" until all the bolts have been started, then tighten them...

If that doesn't work, then drill the hole one size bigger or egg shape it and see if the bolt will go in
Yeah I talked to the guy who built it and he told me the converter was from a late model transmission and that's why I was having problems