I dont know about this....
OMS internships are filled with scut work; and then there's all the other non-dentoalveolar stuff that it sounds like you dont care for: trauma, cancer, pathology, etc.
I think doing private practice with some good mentors and quality CE is probably the best way to learn the dentoalveolar stuff (wizzies, implants) that GPs see OS do. I'm always amazed at the GPs doing full arch implants.
This is what I tell the GP residents that I meet and are interested in OMS:
Figure out if you want to do an OMS program, or if you are just interested in doing dentoalveolar surgery as a GP, because I think the routes are very different.
If you want to get into an OMS program, then do an OMS internship at a program that allows you to study for the CBSE, and one that takes their own interns, not one that you think is going to teach you how to do surgery. This will give you the best shot in my opinion. While there, dont focus on getting good at your hand skills, but instead being responsible, hard-working, communicating well, and amicable (not annoying). That is hard enough when people are burying you with scut work, and you are on Q3 call. No program director is going to be impressed with an intern's surgical skills, and be like "wow, we need this guy/gal so he can show us how to take out teeth like s/he does".