My burb has trailing arms. It's a GMC, too - with no mention of the coil rear on the SPID. I always thought it was optional to have coils on a GMC and leafs on a Chevy and that it would be on the SPID. For my bag setup, I did exactly that -- used 2 schrader valves for several reasons:
1 to eliminate transfer from bag to bag while cornering
2 have some pressure if one side developed a leak
3 save money
4 keep it simple. I only use the bags to adjust ride height while hauling things, not to show off between traffic lights.
