my shaft is too long. take a look at it

zkx14, how long does it take your oil pressure light to go off? That light is on the outlet side of the filter so the filter has to be filled before that light can go off. If you have the long filter and short standpipe, then I woudl imagine that the pump does take a bit longer to fill the space. A good condtion pump will fill that extra space pretty qucikly; my nicely rebuilt pump and newly rebuilt engine with the long standpipe and filter takes <2 seconds from a 30F cold start for the light to go out. Before the rebuild, it would take 5 more more seconds with the same filter type; the oil pump was just not up to it and the pickup screen was pretty clogged.

The filter in this engine can be drained in 2 ways:
- Via the oil galleries as they leak down through the cam bearings and crank main bearings; these are all BELOW the filter and only the standpipe keeps oil in the filter in this case. How much and how long this drain-down path takes, I can't answer; I would think that is pretty slow as air has to work its way back up through the bearings and oil gallery.
- Via the oil pump and pick up tube if there is no anti-drainback valve; the anti-drainback (flapper) valve is relevant regardless of the filter's orientation. The anti-drain back flapper in the filter inlet (the outer set of holes in the filter base) is the only thing to prevent this. How tight the antidrainback is over a very long term, I can't say. (And there needs to be air drawn back past the oil gallery to allow the filter to drain in this way.)

See here for /6 oiling diagrams for both early and late:
http://slantsix.org/forum/viewtopic.php?p=396372&sid=b5518b7bc2e5213ca288c80d6f4d3858