I actually just disconnected the positive for abt an hr, & put it back on and was fine. Drove it on a 2.5 hr trip this morning, & the light stayed out. But I parked in my driveway for abt an hr, went to pay my water bill, & the light came back on. So... I again unhooked the positive, unscrewed then screwed the gas cap back on til it clicked, reattached the positive cable. No more Service Engine Soon light again. I hope that's the end of that, & perhaps it was because my oil was only at 29% left, I noticed, when I did a systems check to see if the oil pressure was good. The gauge said it was, but still.... But like I said, hopefully... No more of that light!
(She's getting a new Motorcraft oil filter & 5 qts of Valvoline full synthetic tomorrow!) If ya got any more feedback, it's definitely welcome.
Thank you for the suggestion, & I'll be heeding your advice, even though it's stayed out - knock on wood
& praise the Lord
(!) - ever since the last post. My mechanic who does my big work for things I can't do myself, like hubs & bearings, who is 69 yrs old & has probably the most well-equipped shop in all of southeastern MO... He'll check to see if I'm throwing any codes, no charge, just like Autozone does. And if I AM throwing any, his labor is only $65-$70 hr, which, if anybody knew how good he was, would understand just how honest & decent the man is! He's as good as God makes 'em in my book! But your advice will be employed, 110%! I sincerely thank ya... 
