RAF Lockheed Lightning (P-38 F/H) Mk.II

[wuzak]

Unless you use the slimline Merlins Rolls Royce developed for the Hornet.  All of the ancilliaries are behind the engine to ensure as small a cross section as possible.  They were available in '43, or at least the prototypes were being bench tested.

The main external difference between the Hornet's Merlin 130/131 was the downdraft carby, as opposed to the standard updraft carby. The water pump was moved to the side of the block.

As can be seen by the experience with the Mustang X (Rolls-Royce's Merlin-Mustang testbeds), the P-51B/Mustang III and the P-40F/L a Merlin could be substituted for a V-1710 with a little reworking.