from my understanding, the 3.0L cranks are pretty much the same as the 2.5L cranks except for the different counterweights due to the bigger pistons. to save yourself all the trouble, just do a 3.0L swap instead of boring out your 2.5L.
Jim Hahn
1996 T-Red Contour SE Reborn 4/6/04
3.0L swap and Arizona Dyno Chip Turbo Kit
364 whp, 410 wtq @ 4,700 rpm