When I swapped from manual to power steering these are the steps I followed. It took less than 2 hours to R&R the box, then another hour to install the pump and hoses.
1. seperated the pitman arm and the drivers side inner tie rod from the center link. I also pulled the pitman arm but I am not sure it was necessary.
2. pulled the starter.
3. Pulled the steering column.
4. Un-bolted the header and dropped it out the bottom. Real easy with the starter and column gone.
5. unbolted the steering box and removed it out the bottom.
6. Placed the new box (power) in place but not bolted down. This allowed me to move it around for header install clearance.
7. slipped the header back into place and held it tight against the block with bungee cords.
8. Installed the three bolts holding the box to the k-member.
9. Re-installed the header.
10. Re-installed starter.
10. installed pitman arm on steering box and reconnected center link to pitman and tie rod.
11. Installed steering column.
12. installed pump and hoses.
Note: if you are R&Ring a power boxyou might want to pull the pump at the begining, it will give a little more working room. Also, no need to un-bolt engine and raise it, I didn't.