I'll go ahead and apologize in advance if any of these questions have already been asked and answered in one form or another already.

1.) Presently it appears that whenever you see B-52s carrying conventional "dumb" bombs, i.e. MK82 500lbs or M117 750lbs, on their under-wing pylons the bombs appear to be fitted directly to the HSABs in lieu of having the bombs fitted to MERs that are then fitted to the HSAB. This configuration seems to limit B-52s to 9 weapons per pylon instead of 12, why is this? B-52s from the Vietnam carried MERs on their pylons that allowed them to carry 12 bombs per wing pylon, why not now?

2.) In regards to B-52Ds fitted with high density racks or the so called "big belly mod" was the entire surviving D fleet modernized to that standard or only part of it?

3.) Was there ever any serious thought given to fitting variants other than the Ds with high density racks? Granted the utility of such a modification in today's world with the wide scale utilization of "precision" guided munitions would be of limited value, but what about before the wide scale usage of PGMs? Perhaps the C model as attrition replacements for D models destroyed by crashes and accidents during the Vietnam era? Given that it was similar to the D model and served in many of the same units that the D model were in it would appear that a C model modernization wouldn't be all that different from a D. Or maybe G models after the end of the Vietnam war when the Ds were steadily retired and the G model picked up the conventional warfare mission?

4.) When G model aircraft were sent to Andersen to support the Linebacker I & IIs operations why weren't their external pylons fitted to carry conventional bombs like the Ds and Fs? Was it a somewhat extensive and time consuming modification that required an extended stay at a depot and therefore there wasn't enough time?

Thanks in advnace.