I've played SS exclusively for almost 10 years now, and I've always used 30" scale strings. LaBella make a special Mustang set for through-body stringing, which I guess are similar to 32" scale strings. In terms of winding round the post, it doesn't matter too much with the D and G, but make sure that only the narrower part at the top of the string (where the silk is/would be) goes around the post for the E and A.