I would fix the 04 the 2000 isn't worth as much and it has basically the same trans that is in your 2004. The 2004 has different electronics in it along with a few other changes.

get someone that knows the 48re and you should have no problem getting 200k out of 1 of them.

70 duster full chassis super pro 416 CNC Indybrock heads 727 w/brake

best so far 1.212 60 6.219 in 1/8 at 110.88 9.768 at 137.81 1/4