serpetine belt systems got a question??

[sam's 72]

I want to run a serpetine belt on my new 383. I really can't afford to go with the March pulley kit. I was wanting to go get a set up from the bone yard. My question is, the belt systems that I am looking at take a new style alternator. You guys that are running these type belts on your truck, how are you setting this up? Are you wiring in the new alt, or using your old alt. I have done converted over to a one wire alt on my 72. I would like to see some picture if possible. I was hopeing to be able to do this and run my alt.
So please help me out here.