Jack,I would recommend you contact Timmy at Mac1, he is the guru on these guns...
Tim is a supporter of this forum and offers his words of wisdom pretty freely, not speaking for him, but I have seen him answer other people's questions on their guns for stuff that he charges to do.He just did the steroid treatment on my gun and it came out great....
I'd becareful about grinding on those parts. I just polished the mating surfaces on mine, the sear and hammer, and now my trigger is a tad sensitive.Jeff
I just sent an email to Crosman to see if the triggers are still available and at what cost.I also ordered a pair of 30mm rings. I have a Bushnell Trophy Red/Green dot sight (four reticle) just sitting around doing nothing useful. Not sure I'll like it on the C9, but will try it. The 2X pistol scope on it now is too far from my eye for quick acqisition of moving targets. It's OK for paper targets, but I'm thinking the red/green dot sight will be faster. Mounted rearward of the rear open sight, it will be even with the loading port and much closer to my eye.
I can sympathize with the issues of scope mounting a gun that's comb is too low for good cheek weld!! I have used a number of things to try and improve it... One that may work for you uses a neoprene sleeve to cover the stock and hold foam cushions shaped to lift the cheek for proper alignment.Another would be to cut the top of the stock flat, then glue on wood of appropriate height and then cut and shape it to a smooth finish. I have done this one too, its allot of work.As for the trigger work, your on to it, just keep going slow. As for the part call or email MAC1 for the part!! Keep after the Sheridan, its a good one and worth the effort to make it better!!I am rebuilding one myself!! With luck I will have a second with in a week... who knows what condition it will be in.. I'm betting the seals will be gone.Good luck,CW