I've looked thru every B-29 book I have or have seen & Googled with no luck. I've read that some of the B-29s sent to the RAF were equipped with racks at the wing roots to carry a Grand Slam bomb under each wing. ISTR also that some USAF a/c were modified as well. I've not been able to find pics or drawings of this installation or use of. Does anyone know if this practice was actually done? Has anyone ever come across any drawings or info? Thanks.