Correct starter doesn't fit 1972 Dart 318

I ordered a replacement starter for my 1972 Dodge Dart 318 from autozone. I went to install it and it wouldn't bolt up and felt "stuck" I found out the field housing end was hitting a brace and bolt on the engine block and it was keeping the starter at a slight angle.

Everything I look up points to this 1972 318 needing the 3258 starter, which is the one I bought. While the old one installed in mine is the one with a shorter field housing, model 3250. There is about a half inch difference in overall length.

I've read about the difference between them. The 3258 is a higher HP model that came along later I gather. Do you think there is a chance that my car has had a motor from older year installed? I'll see if I can get a picture of what I'm talking about.