Essex - you can never have enough toys!
logoman - If you look closer, you'll see that the steam manifold has bolts, whilst the exhaust manifold has screws. There IS just enough clearance to fit the hex bolts, but tightening them is very difficult, I ended up using a small pair of pliers for that! As an engineer, this somewhat goes against the grain, so I'm going to be using the screws until I can come up with a better way to tighten them.