I would try loctite red to glue wingnuts to the ends of two of the threaded rods. Makes quick and dirty "long length wing-bolts". Since they are just hand tightened, loctite red might be strong enough. If not something else like solder, braze, or weld if the loctite won't hold. Been a while since I looked at them in detail. but I think the originals are brazed.
And for the receiving end, do what you had before... Stud threaded into the carbs and coupler on the other end to accept the newly created wing-bolts.
Flat and rubber washers under the wingnuts. Cup washers optional.