LMP1 indipendants to run GT1 6.0 V12 production engines?

[knighty]

ok, so I have just watched the start of the barcelona round, and the main talking point is the Aston is well in the mix with the diesels.......on another post I calculated based on Aston GT1 power figures and restrictor size, that a 6.0 V12 with the LMP1 air con allowance added on, is producing about 695bhp......and I have a tenner that says Prodrive have pushed this figure to 700bhp.......

so whats stopping say for exaplle rollcentre/Oreca/Bob berridge etc purchasing a V12 aston or ferrari V12 production engine, which is a homologated GT1 engine, converting it to LMP1 spec, then go racing........as it seems to me that the aston engine does have the legs over the Judd units now.......admittedly, I dont want to take anything away from the car - the Lola coupe looks pretty handy too.