jzlowrider

I am currently working on a project where I have a new 2015 Ls3/T-56 installed in my 63. I have the engine harness from GM (it sells/is option with the crate motor) and was wondering how best to wire it into or with my stock harness or do I buy an all new "kit" harness. I am replacing all of my stock harness front to back so going with a "kit" one is not an issue. Or do I just buy a stock one and wire in the Ls harness. Any direction would be great.

PS I looked through the threads and couldn't find anything recent. I will post pics soon.