C3 relocate battery

[TCwitaC3]

Hi, I have a C3 1972 SB a/c car. The ac has been replaced with a Vintage Air system so there is a lot of room under the PS fender bbetween the fender well and the firewall. Looking to relocate the batter there to alleviate wiring issures from the Holley Sniper system, vintage air, and electric fans and a Front Runner systems that require you to hook power supplies right to the battery. Would like to get a tray with hold down that bolts to the firewall and fender well. We can modifiy one to fit. I was looking at the 1963 to 1966 boxes that mount there look pretty close. Any direction would be appreciated.
Thanks,