4020 3pt with no oomf?

I have a side console 4020 (69) that my grandpa and his brother and dad bought new. Its has a hair over 9000 hours and is now one of my main horses. I use this tractor for many things but moving round bales (1500 lbs) on the three point is when I get frustrated. In order to pick the bale up at all I have to put the draft selector lever in the "D" position and then it only lifts the bale enough to kind of skid it along the ground which pulls the twine off and sometimes even pulls the bale off the spear. The hydraulics on this tractor are a wreck I will admit that, the main pump leaks the load shaft leaks and the trans pump I suspect is weak as the hydraulics chatter badly when on the clutch at all. I do change the filter regularly and clean the screen about once a
year. I recently had the scvs rebuilt and I reset the standby pressure on the main pump to around 2350 psi at the outlets. Other than the hydraulics chattering the loader and all other hydraulic functions work normally, the 3 point doesn"t settle much and I don"t see any spraying oil through the fill hole with the tractor running and 3 point up. My question is what can I do to get the three point working properly so I can lift bales to the full height? And yes I plan on replacing the main pump and load shaft and seals soon to get rid of leaks. Sorry for the long winded post just wanting to be thorough. Thanks in advance the knowledge and information flowing through this site is fantastic.

The hyd leak at the front could be something else besides the hyd pump. The correct solution to the 3 pt lift height problem would be to adjust the L/D mechanism as outlined in the JD service manual. There are several steps that must be performed in correct order.