The auto parts store will probably have to look it up in a book. I got mine from Autozone for my 292 and it wasn't listed in the computer. I think it was a Wells, part# TU51. Should be the same for 235. ChevyDuty has one sender listed for gauges, years 56-72. It's $2 more than Autozone, $10 vice $8. As for hookup, it's one wire from gauge going to the terminal on the sender. I think the gauge is grounded by way of mounting to dash insert. The same way the single wire dash lights are grounded when inserted into holes.
-David
Kustoms-and-Sleds
