98 Ford E350 question.

I picked up a 1998 E350 extended wheelbase van and wonder if any of you know what trans is in it? Or an easy way to identify ford transmissions of that era?

It is a Triton V8 with an auto trans.

My plan is to search out a Dana 60 front axle (the van looks to have a 60 in the rear) and possibly just slap a T case on the existing trans vs buying a new (4X4) trans?

What ya think folks?
Can it be that easy? Maybe a new tailshaft required?

Is this a terrible idea and I should just find a wrecked 98 F350 and gut the drive train?