PSI single mag drive

can anyone tell me how to take it apart,need to change bronze gear and just scratching my head here..

 

I have a Dunn single mag drive with PSI shaft upgrade....and I had the same issue a few years ago (wanted to install new bronze lower gear)...So I called PSI and they were helpful walking me through the procedure....seems like I did hafta make a spanner tool of some sort but was an easy process....

 

was that tool for the top pulley or pulling the shaft apart?

 

Seems like it was for the shaft....but call PSI anyway....not that complicated after i spoke with them...