I have fitted a 16v in my mk1, use the 8v gear box, 16v clutch pressure plate with 8v disc, use all the 8v engine mounts, engine fits in no probs. Fit the 16v air flow meter to the top 8v air filter case, hook up thr fuel supply and return, use the 8v injector pipes (I had to make up adapters as the injectors had a different thread) the 16v inlet manifold puts the throttle body on the o/s, so you will have to make up inlet pipework from the manifold to the metering unit. Or, fit the 16v metering unit to the o/s, use the 16v injector pipes and re-plumb the fuel supply and return to match. On my car, the dist cap and leads hit the brake fluid resovoir, so I fitted a remote fluid tank. There is a way 'around this by fitting a cap with angled plug ends to clear the fluid tank. I cant comment on the exhaust side as I went a different route

. Have heard that Scirocco 16v parts are the way to go

. 8v starter works ok.
The rest is a few wires and a bit of plumbing, there is other things that I cant think of just now.
Steve.
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