Prepared the left main gear mount and attempted to bolt in place. No matter which side was started first, the other alignments were impossible. The bolt holes were carefully inspected and deburred for resistance. The holes in the corner are off by less than 1/16th inch but it is too rigid to budge.
Need to do some more adjustments and try again when fresh. The holes under the top side are a real challenge under the best of circumstances.
NOTE: Have seen pictures of later RV models and the top edge of the mount is 'inverted' with the angle UP instead of down. The holes are on the top side of the gear mount and easily reached. (This is the kind of thing that could make a builder jealous (and ready to spend money to have these mounts modified.)