G 20 conversion van (1990) heater hoses?

can anyone show me a drawing better than the chicken scratch in chiltons of how and where all these hoses go? i have a rear heater, and a control valve with 4 openings on it, 3 on one side 1 on the opposite.
Please help the kids are getting cold! :banghead:

if its a conversion van most liklely your going to have a vacuum controlled t junction to feed the rear heater try to see if the vacuum line has suction.. this "t" is located on the pass side right where the heatercore is beneath the airconditioning assembly
BTW my rear heat never worked all that great to begin with seemed to always blow cold by the time it reached the rear heater core

good luck