oil pick-up tube to pan clearence

Ok, so I'm putting the oil pan on my 406 and I am trying to get this right before I put the engine in the car and have no room to do this over. Heres the deal... I have a melling m55HV (high volume) oil pump and a Milodon 7 qt. oil pan that measures 8 & 1/4 inchs deep. I have a pick-up tube but when I measure the clearence, I have 1/16 to 3/16 of an inch clearence. The way that I measure the clearence is, I tape a drill bit of what ever size to the pick-up and put some greese on the drill bit, then put the pan on and see if there is any greese in the bottom of the pan when I take it off. What I am wondering is what should the clearence be from the oil pick-up tube to the pan?

Thanks for all the input!