Finally got the correct filter and bypass valve for 560, drained oil in 3 places and surprisingly oil was not that bad, small amount of crud near rear of transmission but noting like in filter housing. Fired it up after adding new oil, pressure still a little over 300 psi at couplers. Can I check pump output directly by hooking pressure gage up to outlet on side of pump housing, one where hose hooks to go up to outlets. Want to eliminate other problems such as relief valve. I have Blue Ribbon Service books, but don't have flo rater available, just pressure gage. thanks for any help