A note on using gen hands with a VR3186:
The gen hour hand clearance to the dial is extremely short. I was able to fit it with a little angle up toward the hand tip but wasn't really happy with it. Then when I pressed the GMT hand on it pushed the hour hand down onto the dial. Ouch.
So I was able to get the GMT hand off by itself but had to put some wax paper under the hour hand and use the dial to lift the hour hand enough to use my levers.
This may not happen in every install but there are other reports of it and if not paying attention it can quickly damage a dial.
An example (source unknown)
So I came up with a fix by using an ETA GMT hand hole surround as a spacer on the hour hand wheel.
The fit was perfect, 2.0mm. The hole surround needs to be sanded down on top and bottom to make the spacer. It's not hard to do, you just have to adjust height incrementally to give the hand a little boost but leave it enough vertical room to grip the post.
I made a few of these and the ring I ended up using (shown above) was bigger in diameter than the dial center hole. After I put the movement in the case, apparently the dial contacted the spacer and was affecting the hand post movement, occasionally slowing it down.
The fix was to reduce the diameter of the spacer to smaller than the dial center hole.
Junk dial
Heads up to use extra care with the hour hand, especially if it's a gen hand!
Undoubtedly some suitable 2.0mm hole washers can be found online. Thin, foil type ones can be stacked, etc. I like to just make stuff if I have a usable material.