Finally got a chance to get back on the '32 project. Decided today was the day to build a battery box to mount on the firewall.
I'm using a 12V 20-amp/hour AGM power sports battery rated at 330CCA, should be adequate for the Goldwing engine. It's a lot smaller than a typical car battery, and only weighs 14 pounds.
Built the prototype with CAD, then transferred the design to 1/8" aluminum. Spent a couple of hours cutting, drilling, and bending up the box, then promptly ruined it trying to TIG the corners. I have never been able to successfully weld aluminum with my Miller Diversion TIG. I do OK on steel but I am incredibly frustrated trying to weld aluminum.
After wasting a couple of hours watching my welds go from bad to worse I finally said **** it, threw it in the trash,and dragged out a sheet of 16 gauge steel.
It only took a few minutes to transfer the pattern and cut it out on the bandsaw.
I didn't take pictures of the fab work, but the 16 gauge bent up really nice in my homemade brake. I finished the bottom bend in the big 6" vise. Welded the bottom corners with MIG, then smoothed and polished them to match the bends.

Holes were drilled in the mill with TCT Annular cutters. Big hole in the center is 50mm, the rest are 40mm.
I elected to mount the Goldwing voltage regulator on the side of the battery box. It's tucked in out of the way on the inboard side, glued a piece of 1/8" rubber to the back side to keep it from moving around.
I will probably send this out to powder coat along with the rest of the fabricated brackets, seat mounts, etc. when I tear everything down for paint.
I'll get it mounted tomorrow. Spent way too much time on it already.