It's hot what AC system to use

I have installed the factory system inside and then purchased an under hood kit from Buchillion Performance PN 6651A http://www.bouchillonperformance.com/inc/sdetail/470/545 I also purchased adapters to connect to the compressor on my hemi truck engine PN 6644 from Buchillion.

I only got everything going at the end end of the summer and barely had a chance to drive it and test things out. I'm not sure what was giving me trouble but it would cool great at an idle and then work poorly on the highway. I know I have some work to do when it warms up again to get everything working properly.