Damrod thanks for the pics, it's a nice mod! Looks fantastic on the green nato, very Vietnam era military feel about it.
I think I might be able to shed some light on the issue. Seel dives use a 29mm dial, or at least the Sd1972 King turtle does and its my belief the same is true for Sd1970 based on your findings.
On the ti turtle the part of case which receives the dial is a tight 28.5mm on a good day. (I had no battery in my verniers)
I turned down a sacrificial dial to 28.5 and it still didn't fit until I realised our friends were sloppy with gluing the chapter ring. You can see where I scraped it away with tweezers before blowing it out. There was another spot where it had splooged out and hardened also.
From looking at your pics do I see a slight gap between the dial and chapter ring? If so check for traces of glue preventing full touch down as this case is very tight for the dial and any glue fouls it.
BTW there was a piece of swarf from the crown hole too I removed. Needless to say I will clean this a whole lot before casing a movement.
The good news Damrod is your nh35 and 36 will go in but only with a 28.5mm dial so get shopping
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