Trying to buy a PSS for my Cal 39 as well, and was not able to get to the shaft log due to the battery box being in the way (was not dressed appropriately at the time).
Not sure what the log size is. Imagine yours is the same with a 1 1/4 inch shaft. Do you know the size of the log, or do you remember which unit you bought? Should be a 2 1/2, but not sure. Any help would be greatly appreciated. BTW, would you send the response to cstrasburger@gmail dot com...? Don't get here much....
1980 Cal 39 MKII
St Michaels, MD