You'll need a little more pressure in the keg than just the eq. pressure at your temp to maintain the carbonation, as it appears you have four or five feet of lift to the beer pumps. If you DL the Draught Beer Quality Manual, it has an excellent explanation of balancing a draught beer delivery system.
Probably about 1 psi over the carbonation eq pressure will do it--I can't access my copy of the Manual right now as our server is down.
Very nice looking set-up--"right and tight"!
Terminal Gravity Brewing,