On-board air compressor

I am about to add Firestone Ride-Rite Air Helper Springs to my 2500HD Silverado. Do most of you that have air bags on their tow vehicle also have an on-board compressor for the system, or do you simply air them up vid the Schrader valve at the rear bumper / license plate area?

And, if you do have a compressor, where is it mounted? My gas pickup had an extra battery tray on the left front corner of the engine compartment that would have worked perfectly. The Duramax is pretty tight on space under the hood.

Thanks for your replys.

Mike