I'm in the process of changing the cambelt on my m20 and am having trouble accessing the engine block coolant drain plug. I have a BTB3 manifold fitted and I can just about see the plug but due to all the manifold pipes cannot find a way to touch it or get a spanner on it.

Can anyone confirm if it is possible to access this with a tubular manifold? Or if not what's the best alternative, empty as much coolant as possible by disconnecting the hose from the coolant reservoir where it enters the block?
It's a prefacelift m20 if that makes any difference. I also have one of those vacuum fluid extractors which might be useful but I'm not sure where to shove the pipe in.
Cheers,



