Well, why did Henri try and buy up some old Courage C60 tubs? Easier and cheaper to replace the upper half of the tub with a rule's compliant one than build an entire car from scratch.
Even if the cars were 100% new, the C60 design ancestory can't be denied. And its possible that some of the Pesca tubs were once Courage C60s at some point. Lola did the same thing with the AMR Lola that Enge nearly wrote off--they replaced the damaged section of the tub with a new one and gave it a new serial number.
Also, in the ALMS, LMS and ILMC, LMPC/FLM cars can run in all races in their own category outside of Le Mans, and the class champion in the LMS events will get an LM24 invite for 2012.