That was exactly it! Had to get a big pair of slip pliers. The fellow I bought it from told me he hadn’t changed oil in 6-1/2 years - I doubt he had change the fuel filter in 10-12 years. He is in his 80s and probably didn’t put 25 hrs on it in last 8-10 years. The ring and filter had grown together. It has 2 pre-separators before the filter - the 1st one ran pure water for a full minute! Don’t see how it ran like it did! THANKS!!!
Another question: I have a shop manual (useless for operation and maintenance) - order a operators/service manual from EBay - think I got shafted! - haven’t seen it. Shop manual says check and fill are same for 6610S - fill tube smaller than a pencil - would take a year to put 56 qts in. After looking everywhere, I assume fill plug is one of bolts in transmission cover? Should have taken picture.