Old control box

Ok heres the deal I had a old alarm in a 1987 k5 chevy blazer when I got it it had no remote I never used it but now that the truck is getting restored I wanna put the new alarm in. I know how to do everything on the new alarm since I have now done a few dozen.

My problem is whoever put this alarm in did a really bad job wires run all over the place and I feel tracing them all out will take a while However if someone had a diagram for the old alarm it may help alot.  I took the box out and its old It has the numbers 1024 D on a little sticker outside and also on the ic chip inside. The box has 2 pigtails each contain 9 wires "18 total" Also it has an antenna wire. The board has 740-2 etched into it. I took a few pictures if that helps. also when the box is removed the truck willnot start it also controls electric door locks. Any help I would be greatfull Thanks