Hi Jerry,
I, too, will be fitting a P38 box to one of my projects, when I get somewhere under cover to work
I already have the parts I think I need:
P38 box with steering arm
Power steering pump (already on my 300TDi engine)
Pipework and reservoir (from a Disco doner vehicle)
Defender steering column
P38 lower steering column shaft with UJs
You will need a Defender or similar steering column as once you remove the Series steering box there is no lower bearing for the column, unless you fabricate something.
You will also need some 8-10mm steel plate to make the mounting plate for the side of the chassis rail, and of course, some high tensile bolts & nuts.
I think, though not sure, you can use the steering rod from the P38, either the extension section from the drag link from a Disco, or, depending on your rules and regs over there, you could cut and sleeve a Series steering rod (or have it done professionally if needed for regs)
There's a bit of a write-up on TerriAnn's site
HERE though that is for a LHD setup.
Let us know how you get on
Cheers,
Robin.