The noises are there when your driving it it sounds like its got big cam and a weber but bad.

The noises would be a bigger problem than the revs.

I can only think that some wires are hooked up in your clutch pedal mechanism, which is shorting out the ignition.

I haven't had it for long mate. When would you hear bad noises if it was seized ?

Is it stock engine in the morris, the Morris a series or ??!
What carbs etc?

When you push the clutch in, the only load on the engine is the throwout bearing on the end of the clutch fork. If it has seized, then I expect you'd hear some bad noises.

Has it always behaved this way?

Hey guys I know this is off topic but I am doing the a14 conversion to my 1200 ute and I'm driving my Morris minor ute while I'm doing the Datsun. But I find it weird how when I engage the clutch on the Morris it drops revs quite a lot anybody know what it is? Or how I can fix it?