Mark, the relay in the back isn't original; the voltage regulator (2nd [pic) was used on Mercedes and Porsche 914, check Bosch #30-051 or 0 190 601 006 (I have no idea if these are 20A or otherwise as Steve mentions). These are available as aftermarket, and probably won't take too long even to find NOS.
The fan relays Steve mentions were Carello, 22.900.000 . I haven't been able to find these anywhere...Lee
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