Building a watch

[Terrinecold]

As I am a complete beginner in watchmaking I started by breaking the first movement I attempted to disassemble (I made posts about that it is an ST 36 I still use for practicing). 
I got a second ST 36 and I managed to disassemble clean lubricate and reassemble this one without apparently breaking anything. I decided that I wanted to make that movement part of a watch so I got a case, band, dial and hands from AliExpress. 
 

So today, for the first time, I kissed a movement put a dial and put some hands. Here’s the result.

 

even something as simple as that, I almost ruined it. And of course, completely my fault. I was trying to fit the movement from below and couldn’t figure out how to make it work. It actually is supposed to come from the top and the top of the case unscrews. 
I almost done the top of the case by trying to pride it open, as I thought it was snapping on. 
 

Now, as I write this post, I checked on the item description, and it is clearly indicated that the movement should go from the front and the top of the case unscrews. 
Anyway, pretty happy with the result.  I think I could cut the stem half a millimeter shorter. But that scares me a bit. Maybe file it instead of cutting it. I don’t think I can be that precise with pliers . 

[tomh207]

When you get to the final adjustment of the stem always take it slow with a file. It is a good practice to cut it conservatively and sneak up on the final fit a tiny tad at a time.

 

Tom

[Terrinecold]

Thanks @tomh207 indeed it made sense that one is better off with a too long than too short stem as it can be shortened but not lengthened. 
I think I’ll reopen the watch and as you mention creep toward the correct length of the stem. 
I’ll also regulate the watch a bit. Compared to before I disassemble and reassembled it it the amplitude seem correct but it acquired a small beat error and where it was before running at +5s per day dial up and -? (Single digit don’t remember which) sideways it is now running at -4s dial up and a -7s sideways. I think I must have moved the regulator a bit inadvertently.