Do you know what water pump you have installed? Some water pumps have the bypass blocked, mainly Weiand pumps. If you have one of those pumps you can use a regular thermostat, but the bypass could have been drilled... You can also use a plate with just a small bleed hole and then also use a regular thermostat. It is still recommended to use the correct one..
Do you have the brass plate under the thermostat?
This thread has some nice pictures..
http://pantera.infopop.cc/eve/...562/m/7101010346/p/1
The Robertshaw thermostat is considered a high flow thermostat.
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.