12V reducer, Fuse Box and Bus Bar?

[cv2065]

Ok...cart is stripped so now is the best time to install these items. I'll have individual headlights and stereo head unit (no amp just yet) that will be running through the 12v reducer. I have the instructions from cartsunlimited, but wanted to see if anyone has installed these and maybe have already posted a step by step tutorial so to speak?

Couple of questions off the top of my head:

1. Where is the best place to mount each item? Diffuser says that it needs to be against metal for cooling purposes, so have some ideas.

2. Little confused on the routing of the radio and lights. I'm assuming that the 12V from both runs through the fuse box (each on their own fuse), then the lights to the light switch and radio running through the accessory on the ignition, with the grounds running through the bus bar then to the battery negative?

Chances are I'm off base on routing this. The instructions don't have the bus bar factored in. Help would be appreciated.

Thanks.