I finished positioning and mounting the vacuum pump today. It was a tight fit, but there was really no where else to put it. It down below the steering column linkage, between the motor and the chassis. I had maybe a 1/4" in either direction to play with when fitting it in there. Sorry, no pictures today. By the time I was done, it was too dark to take a decent picture. I'll see if I can post some tomorrow.
Also tomorrow, I need to figure out how I'm going to shield the motor blower from water before I mount that to the other side of the tray under the motor. I've got a few ideas, but not one that strikes me as really good.