It's not going well, and I am starting to wonder how I ever got myself into this. Sample cow hide scraps in hand, I went to a BOM class at my LQS on Saturday & asked advice from some expert quilters for advice. Then I visited the store where I had purchased my Bernina, and asked their advice. The suggestions ran the gamut from butting the edges, using a strip of fabric backing, and feather stitching the seams, to sewing on top of a full fabric backing.
Leather needles and jeans-weight thread in hand, I tested 5" samples and was pleased. What works best is overlapping the edges, then doing two parallel rows of stitching, just like the stitching on a pair of jeans. Worked like a charm on the scraps, but not on the big pieces.
The pieces that I need to stitch together are roughly 18" x 24". Very very tough to hold them together so that they stay aligned while I stitch. And they are heavy, so they don't want to feed as nicely as I'd like through the machine. And they have fur that switches direction, so I'm sewing with the nap for 5 inches, then against it for the next 5. And the fur flies all over the place when you cut it, less so when you are stitching. Sheesh.
The current solution to the holding together problem is basting glue. I tried it for one pair of rectangles, but applied the glue too late in the evening for it to be set enough to work on. It was dry this morning, so I'll try again tonight when my bovine outlook is a little better. I will also experiment with my walking foot.
If that doesn't work, I might just staple the darned things together and throw some cow pies.