Marshall has a good piece on the FLM09 (LMPC-10)
Here which also includes an in car video. It seems from the article that it is the LS3 6.2L engine that will come in the FLM09 (LMPC-10) and Elan has the rebuild contract on the engines. So there should be no problem for inter series racing, the only niggle may be the headlights that are not required in the FLMS, unless there is to be a retro kit to install them in the older models. Or buy the new nose with the lights for the car.