You shouldn't need to take the manifold off, or having read it again were you trying to get the dipstick out of the way?!

You may find that the starter/oil filter get in the way when coming from below, on the other hand if the car is sitting at the right height it might be the best way to go about it though you'll probably be working by feel alone, have fun!

It's not the only thing that's difficult to get to, just about everything seems to require rubber arms to get to