I tried (sort of) to change from continental to something more modern many times over the years with no success. It takes mental commitment and confidence more than anything, and I didn't have either. Fifty years of muscle memory is hard to break, and when the results don't come easily it's hard to stick with a new motion.
Two years ago, at age 63, I tried again and it started to take. I only made it to strong Eastern, but it was clear that real change was possible. Still the same problem with mental commitment and confidence, but I stuck with it for two years, including match play, and now a continental grip feels alien.
This summer I'm trying to go from Eastern to SW at age 65, and it's much easier. It started when I went to see the coach who got me on the path to change when I worked with him for 4 days while we were in Bradenton on vacation. I hadn't seen him for 2 years, and was all proud to show him that I had stuck with the change, even though it was really only to strong Eastern. He basically called me a pu$$y and said that I should go to SW and quit fooling around. He would not accept my excuses about what I thought I couldn't do. An hour later I was hitting SW with some confidence, although mixed consistency.
Today I'm playing open tournaments and cleaning up with my new stroke. OK, maybe that part is not true, but I'm hitting a SW pretty consistently and having fun with it. I even started wearing black socks.
Good luck.