MiniScribe 3438P jumpers?

Has anyone got a service manual handy for a MiniScribe 3438P? I yanked one from an XT clone to use with my SwTPC S/09, but it won't format, and the most obvious possible problem is the jumper settings. There are four that are obviously for drive selects 0..3, and three others that might be the troublemakers. I've tried some random settings, and in most of them it comes up to speed okay, selects, and then after about three seconds starts a probably unhealthy wobbling, sounding as if it is rapidly seeking a million different tracks, one after the other. In at least one setting, it doesn't always recognize when it has got up to speed, and continues ramping up to a frightening pitch. With the jumpers set as they were in the XT, it selects okay, but I get error messages any time I try to read, write, or format the thing. It still works okay in the XT though. Anyway, help would be appreciated. I've already searched the web quite a bit. Found some specs, and a thread in which people were looking for the right settings to use in a PC, but nothing about what the jumpers mean (or how to set them for an S/09!). In other news, I recently realized that I can upgrade my S/09's memory just by slapping 4164's into the unused IC sockets. I had a few lying around, so it got an immediate 64K upgrate. 192K more is on order. I can still remember when this would have cost money! :-) Cheers! Bill.