bowtiefan,
By looking at your blog I am assuming you are running the straight six only with an s-10 gas tank right? I have a similar situation, only I am running a 350 engine. One problem you will have is the fuel gauge. What I ultimately want to do is adapt the original sending unit into the s-10 tank with an adapter plate. That way the original gauge will read properly. Reason why it won't is two things. 1. the ohms in the sending units are different, 2. the original gauge is 6 volt (easy fix there with a reducer and or an aftermarket 12v gauge) But, having the gauge as 12v still might not get you any readings from the s-10 sending unit because the ohms are different. I have not found any straight answer on getting all three equations to work.
As for your fuel lines. I am not certain because I have not fiddled with the Straight six and or older engines yet (even though I have them). So I don't know if they have return lines. I can't see how or why they wouldn't but it sounds like they don't. The s-10 tank has three smaller lines on it, one is return, one is fuel and one is vent I believe.
The electrical stuff. I am assuming you wanted to hook up your sending unit to the s-10 tank right? again issues from above. But if you try that out, let me know how it goes, and or I'll let you know as I am hooking my tank up very soon. Again I feel like I will have to adapt the OG sending unit into the s-10 unit. You shouldn't need any of the electrical stuff from the s-10 tank if you aren't concerned with the fuel gauge at this point. Your engine has a mechanical pump and will pump the fuel that way.
