Is this what's called the Transistor-Reluctor system with the box that mounts on "the firewall"? If so, I've got the instructions, as well as an unused kit I'll sell cheap.
I think the one that you have MIGHT be similar to this design.
When i worked at the VW Dealer in mid-60's some customers installed an ignition system with box on the "firewall". I think it was called CDI Capacitive Discharge Ignition. There was a red push button on side of box
to change from CDI to standard system. The box had an anodized gold color heat sink on outside of case if I remember correctly.
It was a very early design which did
NOT USE a magnetic pickup like the FSI system. Instead it still used the points to trigger the CDI circuit.
The idea was that the transistor circuit would lower the current
through the points when the points opened, thus greatly reducing arcing and increasing point life.
My '69 and '73 VW type IIIs with stock ignition used standard points which were replaced every 3000 miles when oil change and valve adjustment was done. I never adjusted points once installed
unlike with points installed in Model As today which require adjustment after a couple of hundred miles.
Someone must know how to to make a point rubbing block that lasts 3000 miles today.