Well, no dice I'm afraid. I loosened up the fan housing and the genny strap and pushed the housing back to where it needed to be and fitted the aircleaner on. I then slowly tightened the genny strap back down but there was still a good quarter inch gap between the genny and its mount when the fan was rubbing so badly against its housing that it could hardly turn. So its not going to be that straightforward unfortunately. When I look at the carb from the side I can see a distinct dip towards the front of the vehicle, its just not level and this is what's causing the problem - the crappy manifold. This is the last time I ever try and put any Brazilian junk on the car. I've managed to source a stock manifold with clear heat risers locally so I'm going to go with that instead. I've spent too long cleaning and detailing the engine to take shortcuts with it now, its worth doing right. I may try bolting the Brazilian manifold to the bench and straightening it out, maybe it'll have some resale value. Or I may just hang it up as an example.