Short worksession tonight. I deburred the holes in the angle and the tray for the support angle I made.
Next I had to countersink the holes in the tray portion because I have to use AN426 rivets in order to have them flush for the bottom of the battery would sit in that area. The problem is even though I have a mini c'snk head, it was too close to the battery tray radius in the corner to effectively use. So I decided to do it freehand with my angle drill. It came out pretty good and will work fine. When I drilled the holes in the angle it ended up falling halfway on a tray hole.....no problem four rivets will be more than sufficient for this purpose.
Next after finding some rivets in my stock I riveted the bottom portion of the angle on the side mounting bracket and will wait a little before riveting it to the tray. One step closer to finishing the eternal battery mount project.