options for A/C in AD

[msaintg]

hi guys,
I am finally thinking about adding A/C to my truck.

I have decided that I want an under dash unit (with heat) similar to this one:

http://www.oldairproducts.com/catalo...ge-p-4478.html

but I am overwhelmed by all of the different combinations and options. (they are hard to compare because most don't give specifications like CFM or number of coils, etc.)

I already have the factory compressor on the 4.3L V6 engine that I used to build the truck, but nothing else from the old A/C unit.

Is it better to piece something together? What vendor is best? How do I price compare if they don't include the specs?

thanks in advance,
mike