The fuel system needs to be surgically clean. The tank should have been removed first thing when you had crud issues and hot tanked / sealed.

If there was old gas in one pump, it would be safe to assume that fresh gas wasn't going through it (at pressure, nonetheless). Replace the pump(s), before chasing any of those engine rubber hoses.

K.I.S.S principle applies here.

__________________
http://i193.photobucket.com/albums/z...-RESIZED-1.jpg
1991 300E - 212K and rising fast...