Originally Posted by Irelands child
I have an extruded two pass, 24 inch long mounted on the frame rail of my '31. I also have a temp sender mounted in the pan and use a DPDT switch to the engine coolant gauge so I can monitor both with a quick flip of that switch - both run about 180 degrees F on a 90+ day. You can debate location of the sender, but the pan is the easiest for my application. Couple of photos attached:
If you didn't have temp data on your rig, I'd ask if it has even been actually driven at all! Holy Bat, Bleepman! How do you keep it so pristine? The car underside looks 100% brand new, never been off the show circuit floor! Wow!