Rugo,
I am concerned that a NOS pump may have a diaphragm that is not resistant to the ethanol that is in our gas nowadays. I would get a rebuild kit with the modern diaphragm material and while doing that I think you can rotate the the upper part of the pump so that the inlet and outlet are oriented correctly for your truck.

If the diaphragm fails you dump gas into the crankcase and if that happens slow enough the pump keeps up with the carb and you get dilution of your oil. Don't want that to happen!

Kent


1937 Chevy 1/2 ton
1942 Chevy 1/2 ton
1947 Diamond T Model 509
1951 Chevy 1/2 ton
1950 Chevy COE Model 5700 ~ "Barney" ~ And more pix