That rep handstack is too tall if you compare it to gen: you need to shorten the CPs on the 9015 to bring the hands down a bit and then stake the hands where needed. This allows the bezel to be machined thinner.
Machining the movement holder/ mid-case to lower the dial does not work because then the movement moves down and rubs against the caseback.
The 9.8mm mod is so involved that after doing it 5 times for people, I am tired of it. Maybe when summer is over I will do it again for people, but my workshop is lately turning into a metal machining workshop at this point, and I am spending more than half the day doing things like below pic. I will still do machining as part of a larger project but the prospect of getting dozens of JF 15400s and maching large quantities of JF 15400 casebacks and bezels, and then shortening the 9015 CPs for all of them, and staking the delicate hands for a tighter stack is too much hassle for too little return. Maybe somebody can encourage spongebob to do this mod, if he does not do it already. Domi can also do it, I assume, for EU people.
We all know issuing a factory direct thinner 10mm 15400 V5 or V6 would probably be the ultimate end-game marketing strategy for JF: everybody with V1/V2/V3 will dump their watches and buy the new thinner model, even if they are cursing.
Today's fun: