'72 220D after-glow?

[stimpy451]

It's been in the 20F range when I get up to go to work - this AM I glowed the plugs for 30 sec, started, and then moved the gorilla knob back to the glow position to smooth out the initial start (no more than 5 sec).

Worked great, nice and smooth start-up. Am I hurting anything?

Any colder and I'll start plugging it in. It goes into storage at the first hint of snow.