98 needs improvement

I'm about to aquire a 98 GT, with no mods to speak of. A couple of things I'd like to do, but I've never strayed from my fox bodies...
What is stopping me from using body kits made for 99+ on a 98. Also, what degree of difficulty is there in converting my engine to PI heads, intake and so-forth? Last question, how much can I RELIABLY expect my bottom end to hold up to? Thanks for any help. And if you're interested in buying a fox, see my other thread about a black 1990 gt for sale, she's a beaut.

I'm about to aquire a 98 GT, with no mods to speak of. A couple of things I'd like to do, but I've never strayed from my fox bodies...
What is stopping me from using body kits made for 99+ on a 98. Also, what degree of difficulty is there in converting my engine to PI heads, intake and so-forth? Last question, how much can I RELIABLY expect my bottom end to hold up to? Thanks for any help. And if you're interested in buying a fox, see my other thread about a black 1990 gt for sale, she's a beaut.

Body kits will not fit I mean if you look you can see there are difference at the point they meet.

If you can do a head swap on a 5.0... then you can certainly do it to a 4.6. Just need some good wrenching expirence the 4.6 doesn't make it seriously harder.

Your last question... the bottom end should be able to hold out for about 500-600hp. The block is good for 1500hp the cast 4.6 block is designed for unbelievable strength just need some bottom end parts to go wit it.