Pro tip, order a CR2450 battery holder with 20mm pin spacing and solder that in instead. Costs $1. Then use a normal CR2450 button battery, they are cheaper and can be replaced easily next time.

My model was slightly different JBA-T10A.

After removing the 4 base screws I had to lever the base off with a flat screw driver.

No need to disconnect the power wires, the power socket slides out from the plastic base.

3 screws hold the circuit board.