I found a video of someone using an old Singer machine with chisel tipped needles. I suspect a "modern" sewing machine, even my wife's 35 year old Kenmore, might not be up to the task for leather thick enough for the gusset. I like the idea of hand sewing them anyway.

A stitching pony sounds very useful. Maybe I'll avoid sticking myself as much as I already do with a simple needle and upholstery thread. Glover's needles look pretty wicked.

I also watched a video explaining saddle stitching. Do you cut a stitching groove? With the relatively thin leather for a gusset, it looks like it would remove too much material.

Thanks again for the advice.