Aircraft engines. Swapping and upgrading.

[Jeffry Fontaine]

Was there any images of that B-29 with the V-3420 engines? 

the aircraft was designated XB-39 and named 'Spirit of Lincoln'.

Jon,

Thanks for the information.  I guess it has been a while since I studied up on the B-29 and variants and that particular version is one that I do not remember at the moment.  I wonder if you could pull this off with a 1/72nd scale B-29 and a pair of 1/48th scale P-38 kits for the engine cowlings in a scale-o-rama and kit bash to get something close to that in appearance?