OK, I had some time to kill out of town today. Yes, I went to a different Wal*Mart and looked at oil filters. @#$%^&*&^#$%^, no clearanced ST3950's.
Looked inside some. The ST 3593A's were the crummy old clicker bypass ones. Some of the other numbers did have the extra inlet holes and the plastic center core. However, they looked like they had a steel end cap in the dome end. Ecore with a steel endcap?????????