Temp gauge not working Chevy C15

[TCLARK]

Hi Bob
I was almost ready to buy a new dash board but since the
other gauges work, I will pursue this temp gauge rehab.
I found on the net that I need a AC Delco 1512015 sender
which is used on 6v. gm vehicles. There is one on ebay
for 135 US but I may find one around here even on an
old grain truck. I have a friend who is a electrical
engineer who may know how to adjust the present set up.

I am also working on the wipers, do you know how the vac line is
plumbed thru the dash, see my pic earlier in this thread.
Speedo cable is next, thanks for your speedo info!!

Thanks
Terry