Good choice Buzzy, you'll be pleased when you have it, look forward to seeing your build thread of it.
Colin, probably most likely a round number like that, but not to say for certain that it wouldn't be 16.5mm too.
Yes indeed Keith, this proving ground has been what has kept me enticed for such a long period of time... I've seen alot of ppl (internet friendships) worldwide come & go over the yrs from this particular unique hobby, mainly b/c they didn't have a ready access playground to torture their creations regularly.
That would simplify things greatly for sure Ed, but then also at the sacrifice of the scaled look of the elevated bridge having to lower the center body to line things up, cutting ground clearance immensely... quite honestly, it's a shortcut I'd take if I had to make it myself.