Just a heads up assuming you get your hands on one - it may be difficult to find a battery thin enough to fit inside of a case without modifications.
I have that PCB(G60BLE) and I have so far not seen a case with enough space other than possibly the KBDFans WKL Tofu case that could easily fit a battery with little effort. You will probably need something with at least 5-6mm clearance to accommodate a battery and solder joints / hotswap sockets.
If you’re willing to put in the time and possible expense, fantastic. I would actually love to know what case you end up with. But otherwise, assuming Bluetooth is an absolute necessity, I would probably just go with a ready made board.