wiring in 89 motor to 75 truck

i have a 75 3/4 ton chevy truck and want to put a 1989 tbi 350 and trans. from a one ton motorhome.i have everything from the fuse block to the computer, including the gas tank and all lines.what i have been told is that all i need to do is get power to the computer and everything should work just like it did in the motor home.i asked painless for a connector to hook up, but they say they only make their own harnesses.i dont want to cut into my fuse block, and would not know what wires to cut into anyway.any advise or instructions would be appreciated.  

pm me i have done this swap before into my 79 camaro and have all the diagrams to make another harness. all u need is an ignition hotwire, a constant 12v wire to the battery and all ur grounds. i will help u as much as i can.  

thanks for your time. i do not know what pm means?,but would be glad to know more as far as which wires i should cut into. thanks.  

pm=private message...right click on his user name then click private message to send him a message that the rest of us won't see...like secret spy stuff  

do u have an email address i can reach u at so i can send u the wiring diagrams along with my notes on the swap?  

thanks again, send to battycat44@gmail.com      much appreciated.