Thanks for the info guys, I'll investigate further a change to the 10si or 12si. From a quick look I see there are plenty of options with these, even my favourite Rock Auto has them cheap. In the meantime I'll drive it with the parkers as DRLs rather than headlights... gotta have me tunes.

The accessories are powered from the auxiliary terminals on the side of the battery thru a heavy duty relay activated by the ignition key.

The battery was much lower than where it normally sits so meter probably read <12V not 12.8.