O ring or X ring behind pressure gauges on Impact MK II

[NNMV]

First time post. And fairly new to the PCP world.

So from the research I have done I need new O-ring/X rings. I damaged the original ones by putting in new digital pressure gauges too tight.

I recently purchased a couple Sekhmet digital gauges. And I put them on too tight. I know this because when I refilled the impact the gauges read zero. Yes, I tightened them too much. I even seen bits of rubber when I removed the gauges. Lesson learned the hard way.
Anyway my main question is how do I replace these O-rings/X rings? Does the gun have to be completely disassembled or can I just pick them out of there? And put new ones in. Of course I will have degassed the air rifle. 

 

[M0ist0ne]

Degas, pick them out of the gauge hole, but don't let any bits fall in there. 

 

[NNMV]

Thanks ! 
 

 

[biohazardman]

In the diagrams FX calls for an X-ring to be installed on all of the gauges on the MK2 and M3 and a

B34 19723 Plastic Washer "Thin" for the Impact Regulator Gauge on the MK1.

 

[Revoman]

See this post for a recap of the reason for 'extra' O-Ring listed just for gauges.

M3 O-Ring/Schematic/Ordering Spreadsheet - Airgun Nation

mike