I decided to put a pertronix into my '64 230sl. It is awesome. One has to look carefully to detect it, if you wire it right. The improvement is easy to see when timing the engine. At idle, the timing tended to jump around, still ran well, with the kit- it is rock spot on, all the time. It cannot help but to improve driveability. I restored my car as faithful as possible, but I finally opted for old car reliability. I don't want to be on the back of a truck. You can't buy "original" leaded gas anymore either.
Kits are specific for the type or version distributor. the standard Ignitor series is compatible with the original coil, no change from original look. I saved my piont, I'll donate them to a museum.