Thanks Bob,
Getting closer. I backed that screw all the way out and realized that it wasn’t making contact even all the way in… tested with same results, so I backed the opposite screw out all the way as well… that got my front stitch to a perfect 5 spi. The reverse stitch remained at 10 spi, so I put the bottom screw all the way in again and found it made no effect on either stitch, forward remained at 5spi reverse at 10spi.
I worked the reverse lever enough times to notice that it seemed the lever wasn’t rotating the forward/reverse component as far as it looked like it should go… holding the lever down, I manually rotated the component and sure enough it turned farther until it made contact on the opposite side (lower screw which I had backed all the way out again).
This I traced back to the shaft the lever is on where you can watch the shaft turning inside that component until the set screw there made contact and began to turn it, but losing easily 15% of the rotation. I’m now attempting to adjust that set screw for the better.
I’m guessing somewhere along the way the previous owner lost that reverse length adjustment and found a happy place in setting the forward stitch to match.