real differences between D44 and 8lug D44???

[full foot notch]

alright, front of my explorer is done, and its got a 6lug blazer D44 under there that i got from a local board member

well in the garage i have a 8lug "HD" D44, that was pulled from a 87 V20 work truck, and was going to install the crossover setup i have for the steering on my explorer

but i was wondering what the primary differences between the 6 lug D44 and the 8lug D44, i know about the spindle and bearings difference and all that, but was wondering if the axle shafts were different, IE if the 8lug D44 axle shafts might be any thicker/better than the 6 lug D44, or do they use the same axle shafts and the only difference is the spindles and hubs

cause my idea was to swap everything that was better from the 8 lug into the 6 lug axle since its already under the truck, or still go ahead as planned and install the 8 lug axle, but in the back of my mind, thinking it would be redundant to install the same axletubes and shafts if the only difference is the spindles and hubs