Hi there
I know this has been asked before but the haynes manual description for doing the float height doesnt make much sense to me, is it just a case of turning the carbs upside down and laying them on a level surface so the gasket face that yourmeasuring from is lying at an angle of roughly 45degrees of vertical /

thanks in advance dougie

Just on their side so that the float tips against the needle.

45 degree sounds ok.. you want the floats to drop into the bowls and rest on the springy float pin but not to compress it.