Mike, I have just measured a couple of gearbox trays and frames. The trays are both 8 + 1/8″ inches across the rear mounting lugs, like yours, so it sounds as if your frame is a bit distorted. Both the frames I measured are 7+5/8″ between the rear axle slots, which is a bit LESS than yours, so I’m more than a bit puzzled…. Are your rear frame members perfectly straight ?
Brian
