Dodge Repair: truck problems, head gaskets, transfer case

Question
i am needing to know how hard it would be to change the head gaskets on my truck. also my 4 wheel drive doesn't work. does that mean the transfer case is out or could it be something else?

Answer
I can not give u a rating from 1 to 10 on how hard something is   I could be vary easy to me  but  U just dont get it  buy a service manual and read over what it says   then U judge for yourself if U wanna do it.
as for teh 4x4 part  I dont know   U have not given me any sorta cluse to where to point  u just thats its broke.