understand that everything that bolts to the b23 must come out and everything that bolts to the b230 must go in.

remove the fuel lines at the fuel rail. remove the power steering hoses at the rack. remove the ac lines that leave the compressor at these points; the discharge from the ac condensor, the suction from the evaporator. unbolt the motor mounts from the x-member. unplug the wiring harness from the firewall connector and the ecm. you will have to swap the injectors, etc, to keep the lh 2.1 in the 83. you could replace it with the lh 2.2 but the wiring for the relay is different as the 83 has 2 and the 85 has 1. remove the air duct from the mass meter. do the same with the 85 and everything should just bolt up. once you are done the 83 SHOULD look just like the 85 when you raise the hood. the 85 has a remote p/s tank, the 83 doesn't, so the bracket for the coil, etc. from the 85 need to be in the 83. and make sure the engine harness is in good shape on whichever injection system you go with. any insulation flaking you can see is a sure sign there's lotsa damage you can't see. replace the heater hoses, 'cuz it's easier now. good luck, chuck.