Doing TBI swap to 69 GMC

[67ChevNut]

I am trying to install a 1987 TBI engine in my 69 swb GMC. I have a complete 1987 suburban that I am parting out to do this swap. I have the complete engine, with sensors, computer, etc. I also have a 1989 blazer gas tank that I am planning to use, I have an original 96 suburban fuel pump that I will be placing in the gas tank.

I want to keep the original inside cab wiring harness, my questions are:

How do I make the computer work if I am using the original 69 GMC interior wiring, and the headlight wiring as well?

Is there a special aftermarket wiring kit for this application?

What kind of wiring will I have to do?

I will probably be installing the gas plumbing from the suburban as well, want to make this easy. What other things should I consider for this swap?

Thanks a bunch for the replies.