Ditto that ......
I sourced all the stuff Achipmunk mentioned from
CPP in their kit. Pretty inexpensive; especially if you
get the gear and pump yourself.
I also put their disc brake conversion kit on the truck
along with their firewall mounted booster and under dash replacement pedal brace and assembly.
All good stuff, good instructions, fitted well.
The power steering puts a lot of stress on the old tie rod and old style tie rod ends. So, I used the CPP 1 inch replacement tie rod and modern ends to complete the project.
You should have no issues with the 400 with these upgrades.
mike