Im working on a gen4 5.3L for a silverado 4X2 truck. I have 2 different oil pickup tubes. one has a 6 1/4 " drop from the bracket and the other has a 7 1/4 " drop from the bracket. when i look through the drain bolt hole i can see that the longer pickup tube has about 1/2" clearance from the bottom of the pan. what is the minimum clearance for the oil pickup ? Is that enough or is it better to be a little higher to not suck dirt from the bottom of the pan later on ? site would not let me attach photos