I don't think there's any difference in the actual mounting locations over the years, but there are cosmetic differences in the nose pieces over the years.
As for the engine swap, it's not all that hard, but is it really worth it? Yeah it owuld be nice to have the durability of a 4 bolt main. But, after some modefications, the TPI has it advantages. Plus if you're area ever starts smog testing, or you move to an area w/testing, and you put that other motor in, well then what?