So I recently installed a new Sony Marine Radio to replace our old Broken JBL. Everything works great- but the way the old radio was wired (and now this one), the radio does not get a permanent 12V feed to the yellow wire, so that it saves its presets. Both the red power wire and the yellow wire only get voltage when the battery switch is turned on. Does anyone have any idea where under the steering wheel compartment I can find a permanent 12V connection? It's a 1999 Supra Santera, so I know it's a long shot that anyone knows.

*I'll wire the yellow wire with detachable connectors. When the boat sits for long period of time I'll disconnect it so it doesn't drain the batteries. But when we take it out for a weekend/day I'll leave it connected. That way I only have to set presets and preferences once an outing.

Thanks for any help.