Pretty sure this has been done a number of times, and as far as I know everything is electronic the same except for the DOD plug, but that will just stay unplugged.
Here are a couple physical differences.
- PCV system is slightly different. L76 outlet is on the back of the drivers side valve cover. LS3 comes out of the valley cover, near the passenger side of the throttle body. easy change over.
- water pump is different, need a GXP upper radiator hose
All that said. Why buy a crate engine? Quite expensive compared to redoing the L76.
2009 PBM GT
Under the Knife Again
DOD-delete, , Roto-Fab, BLP Ported Intake and Throttle Body, Kooks 1-7/8 long tubes, XForce Varex Catback, ZL1 Converter, Elite E2 Catch Can, HSRK, Camaro Trans Pan/Filter, GXP Brembos, Cold Case Radiator
Breyton GTS-AV Wheels, 6k HIDs, Holden Steering Wheel and Paddle Shifters, Eibach Springs, 35% Tint
Tuned by Day Tuning