MTD Lawn Flight Help?

Yesterday, I took a little diversion from my lbad and picked up something completely foreign to me but I just couldn't resist. I have never used or even seen one of these working first hand but I just had to have it. The problem now is trying to get some info on it. The i.d. plate on it has some hand scribed numbers on it and I'm not sure If they're all there because there's a scrape out of it. Any ideas as to how old it is? There seems to be a bunch of adjustments on it so I suspect set-up on this thing is critical but I don't have a clue as to where to begin.

Any help would be greatly appretiated...raying:

Shawn