whisky runner,
Presumably, you have a 58-63 261 that is set-up for a full-flow oil filtration system?
Do you now have any oil filter on your engine?
If yes, is it a by-pass filter?
It should not be a by-pass (restricted inlet) filter - that would restrict the flow of oil (and may be the cause of the high pressure readings)? I am clutching at straws.
