Special bodied AC?

I've just come across this old photo that I took in the mid 60's at a race meeting at Lydden Hill. At the time, I took it to be a special bodied Cobra. Is it? I'm pretty certain that it was a road car and did not compete (note no competition no!). Does anyone know about this car, or recall it; I've never seen it again and 40 years later am still none the wiser!

http://img81.imageshack.us/img81/5804/img673b1rv.th.jpg (http://img81.imageshack.us/my.php?image=img673b1rv.jpg)

Certainly looks to be based on a Cobra, the bonnet, side panel with vent, door, wheel arches, and rear wings all look right.