I fought loosing converter bolts and even broke a flex plate years ago. Welded it and the bolts to get through the season. Turned out, it was the situation you describe. In that case, the snout was not going into the crank far enough. A slight dressing down of the snout along with a new flex plate and all was good.

Since then, I have had to dress down the snout of every converter I have bought when putting together a new combo. Now, I don't know if the converter or the crank (or both) is the real issue. But for me, dressing down the snout is the easiest 'fix'.

In my experience, the converter must slide right up to the flex plate. If it must be pulled up with the bolts, the flex plate will be forced to flex every revolution which, depending on the amount, can lead to loosing bolts and possibly a cracked flex plate.