ACDelco 12T11B - I think this might fit in the 261 housing
(this is too small a diameter for the later/later 261 thermostat housing, tcl)"If so, is there some reason a person would want to go with the bigger thermostat?" (posted by Deve)
area = sq inches - I do not want to measure/calculate them
If you calculate them and post them, they might help to understand the purpose of the 261 vs 235 housing (I am guessing).
