Righto I've got a VT wagon with a rebuilt 195 5lt and a 5 speed which wont engage gears...

When the engine is off 'box will select gears fine, all speeds and reverse, no problem. When the engine is running it doesn't. The machine has a new clutch kit, new slave and master cylinders, all bled and adjusted and still no dice. Now obvioulsy the clutch isn't disengaging, as the car tries to move when you push the gear stick up towards first, and does its best to take off when started in gear.

The entire clutch system is brand new apart from the lines, so what the hell is going on here? We're stuck and are gonna pull the 'box out tomorrow and see what the hell is going on...

I just want to know does anyone have an opinion on what the hell has happened? Ever happened to anyone? How do I fix this damned thing?