So most parts in hand: got all the bearings the other day, and fetching the standoffs tomorrow. Then just need all the screws and nuts, from a place just up the road..... so maybe next weekend we'll start assembly.
Current thinking, is to have the Arduino with Ethernet act as an HTCPCP server responding as contemplated in RFC2324 and have the arm do the work. (Error 418 notwithstanding).