going to put a set of water pressure gauges on a pair of 502 mpi's..... where is the best place to put the fitting??? should a drill and tap the t-stat housing?? or is there a plug somewhere else that i can just put the fitting into..... thanks for any help!!!!

My old 502 had a fitting on the starboard side of the block, below the middle spark plugs. (stock/factory configuration).

It's probably a water drain plug on yours. Use that.

ill check that out!!! thanks !!!

The problem with the block drains is the lines to the guage's will get plugged up with sand.

Mine is in the intake manifold near the thermostat. I don't have the stock set up anymore. Try and find a spot near the thermostat.

It's probably a water drain plug on yours.