G'day Greenfielder,
The deck mounting was one of the things they changed a few times in the very early years.
Your rear stay bar is mounted to the deck via a ninety degree twist in the bar. My early girl (and I assume gml's as well) have a welded bar attachment. Later they went to a welded cylindrical bush arrangement.
To that end you'd need to refabricate if needed to keep it looking original. Wouldn't be too hard for someone with a vice and an oxy or mapp gas torch.
No chance the rust will clean up?
Not sure about availability of Honda stickers but I'm sure silensmessor will be able to reproduce them from photos and measurements.
Keep having fun with the old girl!
Cheers,
