Ah yes that looks like a solid state job. They don't generally fail. The other posts were about original generator system sorry.
More likely you have a wiring fault. Possibly caused by the alt shitting itself. Have you checked the gen light globe to see it's not been blown like your stereo?
Taking out the battery causing loss of power to the coil also sounds like a wiring issue. Get a multimeter and check if the battery is charging. Those regs should be cheap and easy to get hold of so maybe worth swapping.
Must be someone on here knows more about autoelectrickery than me. Good luck.
Clay
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Thanks Clay, the gen light it's still fine after looking at it. I'm guessing the surge of power has buggered up a wiring connection somewhere. As the wiring on my car is very old and has had bits added and removed over the last 50 years it's hard to work out what's going on. If anyone else has any ideas please let me know!!
Thanks
James
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