pardon me, i realize that i should have made it clear that i drove the van for 10 years before removing the factory mechanical fan. and it was about three years with just the two 16" electric fans before assaulting the radiator and adding fans and relocating the oil/tranny coolers... the initial oil & tranny cooler install was done many years back.

open this link and read a good explanation for what a balanced thernostat is and does:
FlowKooler Automobile Water Pumps - Chevy, Dodge, Jeep, Ford, and more
(with thanx to the flowkooler folks)

yes the floorboards were picking up heat. i surmised it was due to the lack of airflow due to the removal of the stock mechanical fan. so far, the two 9" fans seem to be moving enuff air to keep temps underhood/underdoghouse from radiating into the floorboards.

fuel economy has slowly drifted to about 14mpg. more if i drive the speed limit.

neil