Yeah my plan for the axles was to try and use the ser inners and civic/integra outers. I highly doubt it will be that easy. I'll probably end up making a collar and welding the two shafts together. Test drive it like that to see if they bind and send them off to a driveshaft shop to see about making a custom set. I've also got some ideas on how to make the welded axles somewhat strong using normal and revese threaded shafts tapped and screwed into the shafts and then welding the collar on there. The threaded rods would serve to try to pull the two pieces together under torsion. Don't know if it would work but I'd probably try that before spending the big money on custom shafts.

As for the wiring I'm thinking about trying to run the stock ecu. I'd run a gsr engine harness and re-rout the wires to the appropriate sensors and splice in the nissan plug for that sensor like on an intake air temperature sensor, for things like the map I'd wire it over to the Nissan MAF. I'd try to match up as many honda wires as possible to where they go on a nissan motor then make a conversion harness from obd1 honda to whatever nissan ecu I end up using. Obviously there are going to be alot of wires run through straight to the ecu but I'm not afraid of a little wiring. As of yet I have not really studied the sr20 wiring diagrams so I don't know know if this idea will pan out or not. If it looks too hard I'll do a stand alone.

Zee, the car I'm talking about using is your old red hatch