What you have is a Murray built Sears. Cheapy, but not necessarily bad. Hard to work on? Preposterous. You will probably never find an easier bike to work on. Nothing out there is as easy to work on as an old one piece crank American bike. You can take it apart with an adjustable wrench and a flat head. No special headset tools/bottom bracket tools/proprietary baloney.

That being said, it is a low caliber bike. I'd put cruiser bars on it, get a basket and make it a grocery getter/knock around bike. A job it is well suited for.

Murray actually supplied bicycles to Sears before Puch did. Puch originally supplied lightweights, and continued to provide some models through the 70s, but because of the bike boom in the early 70s, Murray began to supply more and more of the Bicycles Sears sold. Indeed Sears had such a hard time getting enough bikes in the 70s they sourced them from just about everybody, but Puch and Murray were their two biggies.