GX-E-CS3-1 Builds No Pressure HELP????

Hey guys,

My uncle brought me his GX-E-CS3-1 pump to me to repair because it's not building pressure. First we thought it was a faulty Pressure Gauge but that wasn't the case, a new pressure gauge did the same thing. I've taken it apart and cleaned what I can see needs cleaned but I would love to find a step by step rebuild procedure. There are 2 V-Valves on the bottom of the piston. I need to know the alignment of the V-Valves and Reed Valve. Are there any videos or guides that teach you how to repair this pump or is it possible to repair this pump? I have a 300 PSI gauge that I used for a deadhead, the pump produced 250PSI before turning off the pump. However with 2 standard gauges for the results were the same. I would love to see a complete tear down and rebuild or could pay someone trustworthy to repair it themselves.