Yes, I have to admit I was not sure where else to put it, if anyone can suggest a better location I would be grateful! In the absence of any obvious earthing point I just picked up that existing self tapper, it looked nice and shiny where the thread had been cut, and it torqued up really well. Where have other people earthed their relays? FWIIW my battery is in the stock location.
Ian91, by seat belt mount do you mean on the door piller, below the inertia reel ? That could be a good idea... nice and close...