After owning a Grumman for going on 38 years and being part of the Grumman community I have heard many horror stories of trying to get a nose gear strut out that had not been removed in many years. I have never had that problem as up till now I lived in a relativity dry area. If the strut has been out in the last 2 – 3 years I would not expect any issues unless the last reinstall was not done properly and the aircraft lived in a high humidity environment.
The indication that there was fresh pitting indicates water got into the strut and receiver. This might be a case of not sealing the strut properly on the last install. I do not expect to spend more then 1-2 hours to prop up the nose and remove the strut under normal conditions. Then there is stripping and repainting the strut assuming normal paint erosion on the leading edge.

Rich Harrison
Not an A&P (but my wife is), just a Grumman owner since 1981
Dog is my Co-Pilot

I aquired a79 Tiger that was out of Annual for 10 years. It took us many hours to get it out, we were ready to give up and it started to move. Got it cleaned and back in according to manual. Shouldn’t be a problem if ya do it every 2 years if the planes hanger Ed.

I acquired a 77 Tiger that was legally maintained, but not maintained IAW Grummans checklist. It took Roscoe 8 hours to get mine out. There is a video about it on the Grumman Pilots YouTube channel.

I think it is important to note that it does not have to be removed in order to sign of an Annual in accordance with FAR 43 appendix D. Of course it is better to pull it than to not pull it but if it doesnt come out you dont have to be forced to make a decision at that time. You can put it back together and ponder your next move. Its a risk vs reward situation.