Idler Pulley/Belt tensioner questions

[ukcats07]

Okay, so I've been pulling my hair out over this problem of mine. I've got a 302 and T5 in my 240 (see another thread for pics) and it's basically a longblock at the moment--no accessories. I've got a reverse rotation water pump with the timing cover that has a mechanical fuel pump opening. I've purchased a set of serpentine pulleys from summit (part # MCH-1000) with a smooth water pump pulley.

 

I would like to be able to use these pulleys without running AC or PS. I know I need an idler pulley, or belt tensioner, in order to get the reverse rotation on the water pump. I see a couple scenarios:

 

1. Buy this (link) $80 belt tensioner setup to get the correct routing. However, I have no idea if it will work with me using the old style alternator brackets (these ones) (i.e. will it all line up).

 

2. Buy some aluminum and drill holes, etc and mount a standard 6-rib pulley to it similar to 74_5.0L_Z. If I go this route, what pulley do I need? Cheapest autozone pulley available? Any considerations for making my own setup? Drill the holes, line it up and bolt it in?

 

Also, any need for a 130 amp alternator? This will be carb'd with no stereo system, etc. What year/model should I be looking at for my alternator donor?

 

Thanks,

Doug