C2 Turbo Intercooler

I have a C2 Turbo intercooler that I want to use on my earlier 3.3 engine. Before I spend a lot of time trying to figure out how to make this work, is there someone out there who can tell me what is required. Since the early intercoolers only have two connections (one of which is blocked off) I am not sure what everything hooks to.

What is number 5 for? The intercooler was modified and the threaded connector was welded on by the neck of the intercooler...

Also, can someone tell me what each of the connections circled in the picture below are for

Thanks
David