Uprising,
Can you give us the rough break-down of which parts you are using from each bike (78F, 73K, GL)? It appears you are using the 78F frame, engine, oil tank with the 73K gas tank so far. What is the overall objective/design-aesthetic you are trying to achieve?
It would make sense to use the front end from the GL for the larger diameter forks and brakes, as well as the 78F rear wheel/brake.
Frank: it sure does look that way. That gold tank did look good (patina, flaws and all) but it's uprising's now to skull-ify!