Just an idea I've been toying with, but it seems to work pretty well. The basic idea is to fire the AC5s on chainfire in one group, and the AC2 separately on another since they both fire every ~0.5 sec. Just hold down the buttons for a constant stream of fire. The timing is not perfect of course, and they do get out of sync, but that doesn't really matter, and may even be preferable for constant screen shake on the target. You get the rapid-fire effect of three or four AC2s without the heat issues, and the weight is a bit more manageable than trying to cram four AC5s onto the chassis. AMS or some ammo could be removed for more armour and/or a medium laser or two (if you don't like being completely ammo dependent). This weapon setup can also be done on the JM6-S (see Booty Shaker) and -DD, though it's a bit more of a squeeze. Depends whether you want higher gun mounts or more ammo.
You're an evil man, I like it! I like the high damage potential and the constant shake, means you can go head to head with pretty much anything.
Except a fellow 4X packing 2 x UAC5/2 x AC5, as I discovered to my detriment. But apparently going solo against a Highlander and a Victor together - no problem (though maybe I got lucky ). It will heat up eventually on the hot maps, but you can just take your finger off the AC2 trigger and you should be fine. With Elites, you'll even cool down slowly doing that (110% heat efficiency)!
This is just a plain awesome build. Cool, excellent damage, and even has room for AMS. 5 stars, no question.