Yes- - - -the pump drives off the bottom of the distributor, which is approximately at the middle of the passenger's side of the engine. The late 55 to 62 235s had a similar bulge in the pan rail to clear the Melling M-45 oil pump, but the GMC offset is a bit larger. I believe the vertical position of the pump can be made to clear the Chevy block, and more clearance can be built into the oil pan sheet metal.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!