Hi Andy,

I have converted to 12 Volts and l recomment you a 12 Amp one.

Related with the output from the dyno 6 Volts 45 Watt a 8-0-8 is nearly scratch the end of the scale. 6V x 8 Amp= 48 Watt

This Type of dyno was a pre war construction.

ln The fiftys the rised up to 6 Volts 60 Watt, so you need the 12-0- 12 to read correct. 6V x 10 Amp= 60 Watt

I have an Alton Generator with 12 Volt 145 Watt,so I need the 12-0 12 one.

If you have an output less than 100 Watt at 12 Volt you can fit 8-0-8 one 12V x 8 Amp = 96 Watt

Hope this will help to find a decision.

Cheers Klaus