The front bulkhead is already there, it just doesnt quite go all the way to the hood and leaves a few inches of gap. Closing this off will not trap the heat or anything.....it will still be open for the heat to go out the car.....it just wont bleed into the car above your legs. I cant imagine that will cause any issues.
The rear panel.....I can see some potential there. I figured I would first just make a panel that just covers up the center section between the back panels and the bed plastic because this open area is focusing sound right at your head. I figured I would leave the sides open to still let the motor compartment breath while maybe blocking some sound? I will relocate the air breather as well to cut down on some noise.
The only thing I have to compare to is my brother in laws RZR S......it is very quiet in the cockpit.....I know I am not going to be able to get it that quiet in the Redline with the higher revving motor and all but I figured it could be improved upon some without causing big problems. One could probably build some duct work of some sort to direct air right towards the motor area I would think?