The G&H mount base is installed with three screws and two tapered dowel pins, which require drilling new holes. I just had one installed by G&H, although the one on my MS was on it when I bought it (likewise a .270, which I have since converted to 9.3X62).

The G&H mount is strictly a matter of taste for most people, some swear by it, some at it, mainly because of the additional holes. My thought about the holes is that at least they are not on the receiver ring, where they obscure the lettering. When you remove the scope from the base, the top of the receiver is left entirely clear and unobstructed and the return to zero is in my experience 100%.

Fitting a G&H mount will in general lower the resale value of a rifle, because they are unusual and the average buyer knows nothing about them and their advantages. I own several rifles built by G&H in the '30's, and the mounts are just as firmly attached now as on the day they were fitted.

I live about 120 miles west of Nashville, but usually am in Nashville several time a month.