Here are the choices..
Option 1 : Replace stuffed turbo with a new Isuzu core, enjoy stock power with a little added boost..
option 2: Machine stock Isuzu exhaust housing out to accept my VR4 14b TD05h and enjoy ~20psi with the occasional 25psi while i squirt methanol down it (during swamp action)

Option 3: Replace 14b compressor with 16 or 20G compressor, upgrade to a 8cm exhaust housing and compound with sc14 @~25-30psi
REMEMBER THIS IS NOT A ROAD VEHICLE, normal rules do not apply, Im currently looking at 4-4.5 inch exhaust, any size water to air intercooler.
let your mind go nuts

cheers.