The Building of the Blue Mistic

I am thinking one of these for the heater system (seen on Xtreme 4x4). They look the same, just one is summit brand for $10 cheaper:
http://www.summitracing.com/parts/mar-mm-a1090002
http://www.summitracing.com/parts/sum-991102-1


And this for the A/C unit once i save up a small fortune:
http://www.summitracing.com/parts/vta-672001vhy

The build may not look like it, but I am on a budget. I can spend the money just not a lot at a time. So I am going this route so I can buy them separately and "feel" like I am staying in budget.