Sorry to hear that. I'm worried I may have blown the seals in mine as well. It's expensive to rebuild the cartridge units, but I'll do it if I have to. It sounds like you've done everything you can short of the rebuild; I'd hate to see you quit now.
EFR Twin Turbo LFX-GPI Tune-ZL1 fuel pump-10:1 CR forged pistons-3.45 gear-Meth Injection-BMR Trailing Arms, Bushings & Sway Bars-CircleD 4000 Stall-GPI Fuel Enrichment System
647 RWHP & 726 RWTQ @18.5 psi on 93 Octane (locked converter)
1/8 mile -- 7.158 @ 102.10 (20psi); old build