is the motor blown? have you confirmed that? if you want you can go thru and forge the internals etc. spend some time in the internal performance section and search...lotsa good info on here.
i personally wouldnt bother with a complete rebuild unless the motor is blown. throw a cam in it and go!
2005 Subaru Legacy Gt - Stage 1
2001 5.3 Tahoe LT - Sold
1999 NBM Hardtop Z28 m6 - cam only - 385/369 sold
1998 Black Z28 M6 - h/c/i/e/gears - 392rwhp 375torque sold