1972 2WD to 4x4???

[72longbed]

For those of you that did a conversion on a 67-72 2WD frame, I have a few questions.
Standard or 'Usual' Conversion (GM Dana 44 Front)
For the front:
1. Are the holes for the front leaf spring frame bracket and shackle already in the 2WD frame?
2. Do you have to change out the engine crossmember to a 4x4 crossmember??
3. Do you have to change the steering box to a 4x4 box, arm and pitman arm?
4. Do you need anything else in addition to the T/C crossmember?
5. What other changes/modifications on the front end and chassis are necessary??

I'm trying to get an idea of ALL of the work thats necessary to do the conversion the 'typical' way vs. another idea that I have. I'll be making my decision once I tally up all the parts and labor for the different methods. (Might be overthinking the whole thing but just want to really be prepared before I start the teardown)

Thanks for your help and ideas,
72longbed