Hi Markus,
I am keeping the scrub brake. I am now only to figure out just exactly what Jackshaft is the correct length. I think I can order one 1" wider than the outside of the bearings so I can keep it in by using locking colors on each side. I would prefer to buy the correct length based on the frame model or the distance between the two mounting plates. Apparently the exact one with the snap wring clevis no longer is made, or I just have not found it yet. I may buy the bearings first and measure the needed length of axel before ordering it.
The inside measurements between the two mounting plates is about 8-1/8".
After the bearings go in I can measure what the distance between the locking keepers should be, or add on enough shaft the add two locking colors if it is truly a discontinued part.
OldMiniBikes @ e-bay did clarify what bearings, sprockets, etc are used, however the correct axel length is still not clear and I do not want to do the item return thing.
I bought the frame, wheels, and front end alone. The guy who dismantled it lost everything else. I have found axels, spacers, kick stand, to go with the 6 HP engine I already owned. I have ordered all the other components on e-bay less the jack shaft.
Thanks for your help.