Do the screen if you get bored, but I'll second that 20 psi hot idle ain't bad. I had an '01 Suburban with 3xxk miles that did similar. I think I replaced the oring and de-sludged the pan around 250k, and a lifter would tick after about 3000 miles on an oil change. I just used it as a reminder when to change the oil and kept trucking. Eventually I thought I'd get ahead of it and replace the engine with a lower mile pull-out when it had 320 or something, but it was a mistake, the new one had a cracked head or something intermittent that head gasket sealer in a bottle took care of. Ended up selling it for other reasons, but I think that the original engine would have kept going just fine till 400+. don't remember the hot idle psi, but I doubt it was much higher than 20. All that you need is enough to push it everywhere it needs to go in the engine, and rise with RPM, and it looks like you have that. Run it...