[ainarssems]

Then yesterday he rings at 16:00 having hit a problem with the wiring of the ABS sensor, namely that it's not as expected. A phone call to Dave at Prestige doesn't solve it as he's using the same information source as my garage. So, he's now seeking advice elsewhere to resolve it as he suggests wiring it incorrectly will fry the ECU??

I guess you are putting FL wheelhubs for Brembos as well? ABS sensors are different from PF so that would explain the problem. Anyway ABS sensor wiring is very simple, it's just 2 wires and it does not matter which way around they are. So just cut the plugs off and solder the old plugs on. The chance of frying ECU is next to none, as I said it does not matter which way around the wires are and ECU has protection against shorts. Unless some monkey connects wires to totally unrelated live 12V feed. The sensors themselves does the same job on FL and PF, it's just that they are physically different and use different plugs.