After some phone and internet research in brief moments between work I have managed to get a replacement regulator.
The auto electrical industry appears reluctant to let go of any information related to the mysterious "exciter circuit" and ways to circumvent the use of an "idiot light" to apply the required 2W loading on this circuit.
anyway.. i have found a resistor from
http://www.electricboatparts.com.au P/N 101030 which has been selected specifically for Bosch alternators and for use without the warning lamp. it also has a nice large cermaic heat sink.
You could also use a resistor from jaycar for probably 25cents but the risk is getting it wrong and frying your reg. At $40/ regulator mistakes end up being costly.... ask me how i know.
you could also simply run a 2W globe in series on the "L" circuit if you want a warning light.
Hope this is of some help to anbody contemplating using a Bosch alternator.
Cheers
Ed