1972 dodge dart with oil light flicking

As a flip-side to my and other's suggestion of possible "wire grounding", the following story supports the "gunk on pickup screen" issue.

When I was 13 yrs old, the oil light came on in our Valiant wagon w/ 225 engine during a trip. I knew enough to check the oil level, which was OK. My mom figured the oil light must just be acting up and kept driving, since almost there. She did stop at the first gas station 1/2 mi later, but no mechanic, so kept going. One mile later, the engine poured blue smoke and siezed. She proved you can kill a slant six. Her cousin towed us the rest of the way. He was an AMC Dealer and sold us a used Matador station wagon, a beautiful vehicle and very smooth on the highway. Mom came out ahead. Poor slant was probably crushed.