The classics after line number 703 (first -400 line number 696) have the -400 stab except without the plumbing required to make it a "tank", which is the same as the -400Fs which have a no "tank" stab, the stab is exactly the same the only thing that differs is it's either with or without the plumbing, and as I said blank plates fitted where required like on the right hand underside where the vent and positive and negative relief valves are normally fitted.
These classics also have the same hydraulic architecture for the elevators as the -400 which is different from the earlier classic models, due to the cable runs that run though the internals of the stab on the earlier classics.
I've been in the stab of line number 711 it's a -300 and saw all the various points where the pumps and plumbing would have been installed had that particular stab been destined for a pax -400.
Last edited by SMOC; 7th Jun 2008 at 12:05.