[puddleglum]

ThermionicScott, congrats on the improvement. Sounds like you and I have a bit in common, a short commute in winter weather and a car that's disintegrating from rust. Anything you can do to help it warm up faster and stay warm will help you. With the SG you can keep a close eye on temp so you can potentially block the airflow a lot more than you can by just using a factory temp gauge. I've got mine pretty heavily insulated now and I may go even further for next winter. We are in a deep freeze again and I'm still seeing fair numbers.
As for the SG calibration, it takes a while to get it right and even then it's only close. I found when I had it in my other car, winter to summer fuel made a big difference in calibration. I find it is a big help though and feel lost without it now.