I had a problem with all the ford senders too. I switched to Auto Meter gauges and senders, another option is to plug in a mechanical sender on the block and check the pressure difference.
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.