What to keep of the factory harness??

hey guys, ive done a search and I cant quite figure out the answer.. ls1 going into a 94 chevy, had a v8 in it.. what wires do I need to keep?? I know all of the wires hooked to the motor can go, but what about speedo, tach, etc.. I can see where the wires go into the pcm on the passenger side, do i just need to cut them right there and then cut them again where they go into the firewall (leave a little length of course).. Any info would be appreciated..

oh yea.. got the motor in.. just waiting on the harness and tranny and should be able to fire it up.. This site has been a HUGE help..

Thanks in advance..

Drew

i was also wondering about these wires as im about to swap in my 6 0 aswell.

and did you put the motor in before the tranny????

Yea we put the motor in before the tranny.. dont have yet..

lol makes sense now, to make sure everything fits and all, last night that never clicked thougg. lol. sorry