[jqpabc123]

Interesting --- but it looks like a lot of unnecessary work to me.

Forget modifying the watch itself. Instead, build a strap add-on to hold the NFC payment chip and antenna.

Here is a project where I did something similar to carry a microSD memory card.

https://www.thingiverse.com/thing:6784665

[mrb]

Nothing was unnecessary since the goal was having fun & learning.