DanG,

The outlet is labled 250V 50amp and resembles most closely to the
10-50P on the website you provided. I don't have much experience
switching out breakers so I am going to leave them in place and use a
20amp 240V disconnect at the outlet.

Thank you for pointing out the fact that 240V does not need a neutral,
this is what confused me the most. I kept banging my head wondering
how electrons will flow back if both the obvious terminals on the
pressure switch were occupied by hot leads. It wasn't until you
mentioned this and I looked it up in a time life sereis book on basic
home wiring that I realized the hot wires trade off acting as neutrals.
There is no obviuous ground lug but I do know the chasis of the motor
is common to the clip attached to the metal box housing the pressure
switch since there is continuity when tested with my DVM. So do you
think originally the cord from Craftsman simply grounded the
white/neutral wire in this manner? A consumer would be unaware at the
time that it was acting as a safety ground..right?

The pressure switch block is labled motor on one side and line on the
other. The leads from the black cord (white /black) are attached
correctly as these have never been messed with. I will attach the red
and black to the line side of the pressure switch.Then, I will attach
the white/neural to the clip in the picture as this is what holds the
screw that attaches the cover to the pressure switch.

Thank you for the info
Thomas