Modifications:
A-20A : attack version for USAF
A-20C : licensed version built by Boeing, nicknamed "Boston" by RAF
A-20G : licensed version for USSR, 7,478 built
F-3 : photoreconnaisance version
P-70 : night fighter
A-20G was most numerous verison(over 2800 built)...A-20J had a glass nose to lead bomber formations. trival information for ya.