Hello, and welcome back, here is a frame parts scan, bolt 13, 67-1251, (part 14 + 63 are for sidecar use). If you do not have the original bolt, it should be easy to make one. There should be no need for any spacers between engine\frame, but if you feel the downpipes would line up better by adding some washers between them and frame, this should be no problem (if the trough bolt is long enough to accomodate it all).
Good luck, looking forward to pictures.
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