doesn't look like it's done much work though. Maybe the original owner missed the window to get the update done, didn't want to pay for it and bought a new machine.
Mowermechanic; What Blumbly is referring to is that Victa found lots of faults with the twins when they first came out - one of which is the easiest NON update to see - they fitted a heat shield infront of the carby as they found fuel was evaporating in the lines. Machines without these updates are very rare but usually in good condition I have found as they really weren't used for long before the owners gave up on them (I know - My uncle rushed out to buy one in '74, threw it in the bin in '74 and bought a new machine). There were lots of horror stories.
As Blumbly said; the LM/G4 carby is a good design once you know what makes it tick. It's kinda like a teenage boy. Arrogant and pig headed when it thinks you have wronged it but give it what it wants and it's nice as pie.
As to your question; make sure the carby is put together properly - sounds like it's flooding badly - check your needle moves freely and seals the fuel when the float pushes it up. After that remove the plugs, pull, pull, pull to clear all the fuel, put it back together again and try again.
I'd be getting that one running, finding a catcher and leaving it original - no restoration. Just a clean up. My opinion machines messed up most of the time on restorations when they start out as nice as yours!
Pete.