Hey folks

I need to remove the back from my Chronospace to change the battery but I have stumbled at the first hurdle.

I've tried many options but wondered if anyone else had any ideas?

1. Tried blue tac - No movement
2. Bought a cheap set of dies from Amazon - None of them fitted.
3. Have seen a couple of folks on Ebay that (I assume) make their own dies - Neither have the size I need)
4. Cousins dont seem to stock the size either.

Other than sending it off to Breitling, does anyone else have any other case back removal ideas (or even the right tool I could borrow - Happy to pay a deposit, return postage etc).

(for the record the case number is M78366 and I am measuring 39.2mm from one of the flat sides to the point opposite (its a 15 sided case back)

Thanks
Neil