Front Differential Issues, Please someone!

I have a 1998 Ford Explorer 6cyl. 4.0 4x4. The bearing in the front differential needs replaced. I know that there are pullers out there for jobs like this but there is only about and 1/8 of an inch gap around the bearing for the claw to fit in. Besides I don't even know if the bearing further into the differential is bad to. So what I was wandering is there any way to fix this problem without having to remove the differential from the truck and take the whole thing apart? I don't have the experience needed for this job or the money to get it done proffessionaly right now and it is my only vehicle. So I was also wandering can I somehow disconnect the drive shaft and drive off the back differential, 2 wheel drive? I have a switch that changes me over to 4x4 that I only use in the winter so I don't drive that way all the time, and it isn't all wheel drive. Will it be safe for the truck and me? Can it be done? I know you can change all wheel drive to 2 wheel drive but, can I do it with a 4x4? This truck is my baby, I can't see buying a new differential for a twenty dollar bearing. Thank You.