MrCab I see water vapor(moisture)on 1st crank after setting from one week to the next also.

I try and put the hose for my vacuum gauge on one side and pull vacuum and the pop off valve on the other side.If I mount the vacuum pump on the drivers side I like to pull vacuum from the passenger side,I do not think it really matters but find it's best that way to help keep it from spraying a fine mist of oil out the top of the filter when its at max pressure.

PS If I run one off another Big Block Mopar engine with the valley plate like Indy,I will pull vacuum from it as close to the center as I can get.