I have the opprtunity to get a 96 GSR shell. I have a 95 LS, so i was wonderin aside from ecu, exhaust and cluster, what else would i need to swap my B18B into the gsr shell. Any harness or wiring trouble? Im also unaware of any OBD problems/issues, if any. Info is MUCH appreciated.

 

Unless you're not competent enough to shift before the redline that is indicated on the GSR tach, there's no need for a cluster swap. GSR/LS exhaust is the same with the exception of the second O2 sensor for OBD2, wire harness works the same, just don't plug in VTEC/Knock, re-pin the distributor, and run OBD2 injectors.
ECU problem could be easily solved if you just run an OBD2 P75 ECU or you can run a jumper harness to run the OBD1 P75.

1 suggestion: LS/VTEC with OBD2 head.

 

Not sure where you live, but I don't know the legality of putting a '95 motor into a '96 body.