782D/D600 Compression test adapter?
 

I love my 882, so I recently picked up a long neglected 782D. It hasn't run in 10 years or more, but I rolled the dice (and probably paid too much, but that's ok)..
I flushed the fuel tank, replaced the dead fuel pump, replaced the missing water separator and all of the fuel supply lines. I can't get it to hit a lick!
I've bled the injection pump and am manually powering the glow plugs.
I'm at the point where I don't want to invest more money in it (starter upgrade, battery, etc.) unless I can verify the engine is sound. It's got good cranking oil pressure and "seems" to have good compression, but there's only one way to tell for sure.
I have a diesel compression gauge, but can't seem to find a correct compression test adapter. The CC/Kubota manual isn't much help as far as the correct tool. Online listings are vague and not much help, but here is what I've come up with:
-SG TOOL AID 35550 ADAPTER, DIESEL COMPRESSION TESTER FOR KUBOTA 10MM
It is the correct 10x1.25mm thread pitch and the length looks right, but none of the illustrations show where the sealing surface is. Possibly on the tip of the adapter? Comparing it to a glow plug only tells me...maybe?
Can anyone verify if this is the correct adapter?
Any input is greatly appreciated. :beerchug:

Did you bleed the 3 fuel lines individually?

Yes, I did.

Here are the specs on the GP's. Looks like it is correct if you go to "Specifications"
https://www.ngk.com/ngk-2031-y-103v-glow-plug

Here is the kit the pro's use. Looks like it seals on the face of the adapter.
https://www.harborfreight.com/master...kit-57588.html