CARC oil level filler bolt

Every time I clean and air blast this area there is still a lot of debris in there and its a pain trying to make sure none of it falls down into the CARC.

Is there a cover or alternative bolt that will cover the gap around the original and stop the rubbish getting in there? I have tried grease but that washes off after a period of time.

Something like the caps that go onto bolts in furniture but with bigger cap.

Any suggestions?

In all honesty I'd just suggest giving the whole plug area a good rinse with degreaser and then hit it with the air pistol. It's what we do.

If you want to be *Certain*? After you've refilled it and got the plug back in smear the top with clear silastic. Yup, you'll have to dig it out next time. If you are really this paranoid it's probably a good move.