Just an update: we visited Ed and Kay's on May 23, 2008 (and again when coming back through Benton on May 25, mostly because of the PIE). They now do accept credit cards, fyi, so you might want to update that detail. We told the waitress that we had heard about the restaurant on Roadfood.com; she remembered your visit and your setting up to take pictures of the pies.
As you guys say, the pie was incredibly delicious (we had coconut cream and pecan the first visit, the coconut cream being the best we had ever had) and chocolate fudge on the second visit. The chocolate fudge oozed onto the plate so it was more like a chocolate pudding pie, but who's complaining.
"Behold: an Ed & Kay mile-high meringue pie"
"Here is a slice of the lemon meringue pie. It quivers when the waitress sets it down on the table, and tends to fall apart as soon as you touch it with a fork."
"PCP = pineapple, coconut, pecan"
"Family-owned since Pat & Inez Newcomb opened the place in 1952, Ed & Kay's is located just south of Benton on the access road to I-30. It has won statewide awards not only for pie, but for best coffee and best waitresses."