I'd really like to know how useful it is to add tuner bushings to the headstocks of these old Strads. This is not to add value in $, but in utility and happiness during use. More better is more happier, and if it only costs a few $, then it stands a chance of being worth while. But I've never done such a thing and don't know what the sensitivities are. Does a body need a specially sized reamer to get a tight fit? a reamer specially sized to the bushings? A competent luthier?
My original Strad-O-Lin had bushings on it already when I got it in 1972. Since this seemed to work well, I've added bushings to several Strad-O-Lins over the years. It did tend to make the tuners move better. Some of the original holes were not always drilled very well. I use the small ones available from your standard sources, and are very inexpensive. I have replaced the tuners on a couple of the Strad-O-Lins with new Schaler tuners, which work very well, and when I did that, I used the same bushings that would have been on the Strad-O-Lin originally, as opposed to the huge bushings that come with those tuners. As always, if you aren't comfortable doing something yourself, find someone you trust to do the work.
