Rough Idle Problem- 1967 Valiant

That 4 pin module is most likely a Bosch "021" ignitor. Cheap and common. This module is in my "ready to run" ECU-less LA distributor.
View attachment 1716092589
Pinout:
3 distributor
7 distributor
15 12V
16 Coil Negative
Case ground/earth
I think that's the same module a lot of the Skip White distributors use.