This is a picture of my set-up. (`74 T120V)
This is apparently from `69 on.
Your manifold is different to this.
But its not shown in my `72 or `73 spares books.
[it must be in the `74 T140 book which is in the workshop]
The cup is 70-9555 and the rubber insulator is 70-9554.
This is a far better method of fixing the carbs...you dont need to crush the rubbers much.
The nuts are 1/4 UNF`stiff nuts` I think.
The gap between the manifold and carb flange is due to the `thick` O-ring.
I imagine you could use the cups and rubbers...not sure about the O-ring or nut.
Your nuts may be a different thread???