Seafire FR.47 lower cowling long carburetor intake?

[jjp_nl]

I am currently starting up works on an Airfix 1/48 Seafire FR.46/47. Depending on which version I decide to make I need to use wing folds and the lower cowling long carburetor intake (both for the FR.47) As I was sifting through my spitfire/seafire reference material I was beginning to get the impression that the long carburetor was not installed on all FR.47's? Can anybody confirm that this was indeed the case and if there is some sort of reasoning behind one aircraft having the longer intake and another having the shorther Mk.XIV style intake? Is it something that depends on a particular production batch, or perhaps an optional thing that could be installed depending on the theater of operations (not unlike the Vokes trop filters on Spitties and Hurries)?

 

[tomo pauk]

From what I can gather,only the prototype (PS944) was featuring short carburetor intake, the rest having the long intake. From Morgan Shacklady's 'Spitfire'.