I agree an LS swap would be slick, but if you think it has adequate power for what you are using it for right now, just swap in a rebuilt block until you are done with school and can afford to do a nice 5.3 swap.
While he's doing the LS swap he should go ahead and do the one ton axle swap....
-Karl
2006 Chevy K3500 4X4 - No J.B. Weld on it yet!
1982 thru 94 F-Series "The Klogger" AKA Transport on the road, on the trail, or on the trailer!
1965 Chevelle
1975 Corvette