I have been asked alot about the special drain plug washer i use to seal the sector adjustment screw... i buy these from my wagon lady who supplies my shop w/ misc bullshit. After getting so many requests for them and not knowing any part numbers etc i asked her about them... it is a dorman product part number 097-025...or. 65274..
I pay .50 each through her but doing a quick search amazon has them with free shipping for $5 quantity 2 or one can maybe go to their local parts jobber and find it...try a google search..
Dorman 65274 Metal/Rubber Oil Drain Plug Gasket, Pack of 2
https://www.amazon.com/dp/B00062YSF0..._z3hWyb05YCSP1
They work great and are undetectable once installed....
Hope this helps out..