What is this on my L2201DT?

[Hazelfarm]

...and how do I adjust it? The parts schematic I have is for the L185DT where there is a relief valve bolted on the same place, but this thing is a mystery: no moving parts, some blind galleys. Only possible variable is the depth that the 2 bolts (arrows added to photo) would control. Now that I've had them out - & replaced all the o-rings on the unit - how will I know I got them back in to the right depth? The felt pen marks got cleaned off.
Have had this tractor 11 years, but this year the 3 pt hitch began acting-up until it wouldn't lift it's own arms. A winter shop project just finished successfully yesterday. There were 2 little chunks of rubber & a 3/8" x 1/8" bit of hard plastic in a galley of the "068000 CONTROL VALVE" - the one that goes to the check valve. That's the control valve mounted to the bottom of the top of the
Transmission Case.
So do we call this thing a "relief valve"? How to adjust?
Many Thanks in advance - for somebody's superior knowledge!

 

[bky]

If i was to guess the plugs could be removed for hydraulic hoses for a front end loader. It is just a guess though.

 

[jbeenemd]

No adjustments there!! Those are attachment ports for hydraulic hoses. My L185 has a similar port for hoses that go to the front of my tractor for either a front end loader or in my case a grader blade.
Jackie

 

[Hazelfarm]

Many thanks, Jackie, but I'm still a tad confused. My FEL control for the bucket is mounted on a post beside the hand throttle - all after market for sure - with nary a sign of any other plumbing going back to the transmission case except the steel line & oil return to the oil pump.
Then there's that picture in the parts list of an entirely different part bolted on where this cigarette-pack thing of mine is, and they say it's a "relief valve"? Don't know how I could change this sow's ear into a silk purse -or even if I need to!