How well does it cool? I've been reading a bunch about AC b/c I'm actually in the process of installing a brand new system into my Fox. I've been weighing the pros and cons of R12 vs changing it to the 134a. It looks like I'm going with the R12. I was advised against converting it to the 134 b/c apparently these Fox systems were fairly marginal when they were new and 134 would leave me pretty unhappy with it's performance. I've been posting and reading on specific auto ac forums.