wiring help

[reivaxtorres]

hello everyone, i own a mustang but my friends own 240's and Zs, and ive become somewhat of a fan. im posting on here because one of my friends has a 91 240sx with an r33 rb25 installed in it. problem is the shop that did the swap wired everything wrong (blew the ecu once, and then kept blowing ignition fuses) and they are no longer in business ...what i wanted to know is if its somewhat easy to re-wire the car for the RB and what i would need to do his at home (yes, if its easy enough i wanted to attempt it, have some electrical knowledge), or if there are any shops that just sell a modified harness for the swap. any help is appreciated, he has had his car sitting in the garage for over a year if not two, and i really want to get it running again. i loved the way that car drove

thanks in advance,Xavier