they're forgiving for the most part IMO... GM puts them slap in the open in the new trucks, so heat isn't and issue plus they are sealed up well with gaskets on the connections. make you and enclosure and stick it on the firewall... or if you can, put it under the seat. but aside from static which will kill them QUICKLY, they're pretty hardy.
02 Sierra... motorless for now.
02 SS.. stock bottom 4.8, 241's, 224-220/116+4, 918's and pushrods, front mount turbonetics 78mm, HKS GTII, TiAL, eBoost2, Yank PT3600, Performabuilt 60e, solid motor mounts. Tuned by me with HP Pro and LM2/AFX