If I recall correctly the recommended shock strength was 90 lbs for non wing and 110 lbs for winged cars. the gas expands in summer heat increasing pressure. The best solution IMO is Mark's (IPSCO) relocation kit that relieves the stress off the hinge area of the decklid.
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.