No problem friend.

You said "Spindle length seems to be an issue because of head stock width." I think you meant the thickness of the headstock? If so I found a similar problem of "fitment" with the six of the twelve tuners on the face of my 360/12. The shaft was long enough, but the banjo bolts (the hollow threaded hex head tube that surrounds the tuner shaft and fixes the machine to the back of the headstock, through the face) were too short. There are three lengths available and the keywinds can be ordered with any of the three lengths (12mm, 13mm, 17mm). Most ship with the default 13mm long banjo bolts. You will need 17mm banjo bolts for the thicker RIC headstock. Though nobody confirmed this for me, I would bet that the boutique stocks their M6 mini's with the longer banjo bolts. The boutique was closed when I sourced my set. I do not know how the locking tuners compare with regard to length. I have always locked my strings by winding it over itself and in almost 50 years of playing I've never had a problem with them slipping after the initial new string "stretch out" period. Never used locking tuners. I wonder now, how am I going to lock the octave strings on my 12 string??? I'm in agreement with the "dive bomb" vibrato theme, but then why would anybody put somethng like that on a RIC??? Bottom line on a RIC with locking tuners: I don't understand why anyone would need 'em!

P.S. I also do little British cars so I am very familiar with terms like "fitment". boot, bonnet, drophead coupe....but this is off topic isn't it. Oh I know how to save this, the term banjo bolt is also used to describe the "fitment" of the oil passage on the front ot my Mini's engine!

And on a couple of greasy British motorcycles I own.

Thanks for the banjo bolt info. My 620 stays in tune fine, but It's like power windows in a car. When you experience the ease it spoils you. I find traditional stringing with the floating tail a tedious process. If anyone has a technique, please share. The string keeps dropping out of the tail.
Thanks for all the feedback.

I think I hear those the last time I watched Mary Poppins.

I'll say that I'm not looking forward to restring my 620/12. I'll probably refer back to this sometime soon.