Hi
My digital scales give me slightly different readings each time but the average of five is 3.60 (sorry, that's wrong i meant 4.60) kg (cheap filling station tat!).
The min-etune system doesn't use any screws so when i decided to replace it i had to think long and hard about whether to drill screw holes in the back of my guitar.
I looked at loads of videos and forum posts about the best options and decided against the Kluson style as they need two holes per tuner. I'd settled on the Grover rotomatics as they only need one hole per tuner and that hole is covered by the min-etune if it's ever refitted.
Then i found that the Gotoh tuners are a direct replacement/copy of Grover rotomatics and the 510 locking tuners have really good reviews so that's what's on.
So, yes, there were six holes drilled in the back of the guitar for the tuners. They'd be covered if the min-etune was refitted.
And a meet in Hertfordshire is still on the cards. I've got a couple of trips planned in June but I can always take a run down with a day or two's notice.
Hope that helps 😀
Thanks again for the enquiry