Thanks for that, Chuck! I'd forgotten that Sea Island-built 
Cansos also had BuAer designations. I've decide that the entire USN 
Fortress concept has cursed me. First the pixels fight me all the way, then historical accuracy tramples all over things.
So, I am officially ending my do-no-research holiday ... after I post the next one  

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English Electric (BAC) Thunderstroke F.Mk.1I had a notion of a slender, paunchless, single-engined 
Lightning. Doubtless, EE considered such designs but this was to be one of my 'no research' projects. So ... all pixel-pushing, no accurate facts.
I'm imagining this slender 
Lightning - which I've dubbed 
Thunderstroke - to be powered by a single DH 
Gyron or similar turbojet of the era. I've moved the main undercarriage to the fuselage - mainly to free up wing space for fuel but also to provide more space for pylons.
The pylons shown are a new belly type (shown on both views) plus four underwing pylons. The 'airborne' view also shows optional overwing pylons fitted (and armed, although these are based on 
Lightning overwing drop tank pylons). I'm imagining a typical weapons load of 4 x AAMs. If three drop tanks are required, one pair of missile would go on those detachable overwing pylons.
Other mods are a vertical tail more akin to early 
Lightnings and resized ventral strakes. With the paunch gone, I'm not sure if the strakes are needed anymore ... but it looked a bit peculiar without them.