Correct pitman arm for steering box swap??

[indymachinist]

Hey guys, I have been trying to search and read but I am having a hard time coming up with what I need to do.

I have a 68 c10 with a manual steering box and I am trying to replace the box with a power one from an 87.

Do I use the pitman arm from the 87 power box or do I need to get one from a 68 with power steering?

Thanks for the help