There are some errors in this thread that need to be addressed. Sorry to step on anybodys toes.
The L2 head will fit and work on a E2E. It will not be at full brightness with 2x123 primarry cells. With 2x123 primarry cells it is about equal to a Surefire U2 on level 3 or 4.
I recommend against using 2xRCR123 with a L2 head in a E2E body. I tried it for a few seconds and does work and it's very bright, but 2 CPF members have let the magic smoke out of the Luxeom V by using this setup.
If you want more information on this setup do a search for E2L Error lights. At one time Surefire shipped a bunch of lights that were supposed to be E2L, but many in the shipment had L2 heads instead of the KL1 heads.
I had read about a CPF member that bought a E2L with what was probably a L2 head at a military store.
I was talking to Dan Legg at Tactical Warehouse at a later date, when he told me he had recieved some E2Ls with reflectors. I told him what I thought these might be and that collectors might want them. He looked closer and saw that they were infact Luxeon V. He talked to someone else and then decided to sell them on CPF rather than return them to Surefire. I think there were 50 lights in the order Dan recieved and 46 of them were "E2L Error" lights. I bought one of the "E2L Error" lights and it is in fact a L2 Head.