Cummins downpipe heatshield and turbo heatshield
 

Anybody suggest anything? I've thought about custom sewn insulation, but I think the price wouldn't be worth it.

Good or bad experiences

Anybody

I have some hi temp exhaust wrap on mine, to protect the A/C box from the high temps produced by the turbo and downpipe, works pretty well. You can get it at just about any auto parts store.