Gas Path..correct.....you are probably the same age as me!! Look in D. P. Davis' book Handling the Big Jets the schematic is in there......though he even mentions the 'Load Evener' system originally fitted to the Wing Gears and not used in service to my knowledge...Agree a brilliant aircraft
and a pleasure to work on....Unlike the torture endured by those of us who tried to keep in the air a certain 3 engined, 4 hyd system wide body previously mentioned!!!
I believe the 'Standard' 4 EDP/4ADP/1ACP pump distribution on the Classic became a 4 EDP/2ADP and 2 Electric Pump/1ACP system on the -400...progress, and 2 and 3 systems of course do not really need the 37 gallons a minute 'flow' of the EDP/ADP.