MXS Caterpillar compression brake jam nut

Did my overhead today and #3 jam nut stripped on lash adjuster when I backed it off. I was able to set the lash @ 27 thousandths but jam nut just spins. Can I just run jakes on stage 2 until I get it fixed? Can I even replace screw and jam nut without removing housing from cylinder head? How screwed am I?

 

It won’t back all the way off the screw

 

Can I run with it the way it is if not using Jakes?

 

Thought about attempting to back screw all the way out but afraid piston might fall.

 

Jam nut is back off so far I can only get a couple threads on top, I don’t trust double nutting it. I just wanted to know if:
1. Can I run if I don’t use the Jakes for a few days
2. Will anything fall apart on me if I attempt to back screw all the way out to replace it.
I think I can get a new Cat set screw and jam nut today I just hope the Jake housing doesn’t have to come off the head to swap out screw. I was reading on some Internet forums that you’re not supposed to back Jakes off more than a half turn or so or your Jakes piston will fall apart or loose oil (whatever that would hurt)