Insulation, Radiant and Vapor Barriers - RB's and Recessed Lighting

I am in process of redoing my southern facing cathedral roof. After inspecting the area under the decking, I found that the cavity was completely filled with insulation. I would have to double check, but I believe that the joists were 2x10's. My plan thus far is to strip off the old decking (half rotted), lay down a perforated radiant barrier of the insulation and joists, then add 2X2's over each joist. This should give me a 1.5in air space over the RB. So here (finally) is my question: I would like to put some angled recessed lighting in the space. The ICAT cans have a depth of about 7.5 inches. How far away should they be from the RB? Should I put insulation back over the top of them, to fill the gap between them and the RB? Is this a bad idea entirely?

Recess lighting in cathedral ceilings is a bad idea. It is the heat that the bulbs produce and the diminished amount of insulation around the canisters that usually creates the moisture problems. There are other options with lighting that can produce the desired affect you want. Such as low voltage lighting. These do not get hot and take up much space as IC's in the ceiling cavity.

Thank you for the advice. I will look into the low voltage lighting, but I would think that the amount of heat generated would be the same.