Spindle swap ?

Hello to everyone in here. Ok I have 98 silverado 4x4 wich I changed the rear end couse the old one was busted and the new one was given to me for free together with the front hub assembly. The new ones came of a 93 gmc 3500 as you all know they are 8 lug pattern compared to the old 6 lugs. I dont want to buy adapters for the rear so my question is the following. Is the 8 lug spindle any different in diameter from the 6 lug? I know the axels fit from the 6 lug so im just wondering if I can buy knew hub bearings like if they were for the 6 lug and just swap the spindles. Would this work, any help and advice would be highly apriciated. This is my first truck ever so I'm not familiar with the kind of swaps there is out there for 4x4s.