I wouldn't really woorry about the heat. Grab the pipe back there after it's been running a while. It doesn't get that hot. Your bigger worry should be if it rubs thru the hose. As long as you have enough clearance so it doesn't rub as the suspension travels, you are ok.

 

You should really use the reverse loop specified for 64-66 dual exhaust cars. The single cars had the brake hose looped up, toward the exhaust, while the dual cars had the hose looped down. You would need the axle housing lines, shorter vent bolt (or re-thread and cut the one you have) dual hose, hose to frame bracket, and brake line extension.

You can get most of this anywhere, but Glazier's makes the bracket and extension.

 

the tail pipes get warm but not extremely hot, the main thing you want to be concerned with is the pipe and hose not rubbing

 

Exactly.