I've just been told about this thread and Larry Clain's sad death last year. It's awful that his cars haven't been recovered but I may be able to help with efforts to find one of them, the Lola T400/Frissbee. I run OldRacingcars.com and we have a page dedicated to the Lola T400 (
http://www.oldracingcars.com/f5000/lola/t400.htm). This page comes out top of any Google search so if this car is offered, chances are that any potential buyer will read my page before they buy. Larry's car is the only one which hasn't been located so there is no chance of anyone being able to bring this car to the market without raising suspicions. I was about to alter the page to state that the car was stolen but then had a second thought - should we be more cunning about what is put on the page in an effort to flush the car out? If whoever has it realises that he has no chance of selling it, it may well be parted out instead and then we'll never find it.
I am open to suggestions. Maybe email is best: allen[at]oldracingcars.com. Maybe the mods can delete this post once I've made contact with the appropriate people to take this forward.