Outer Limits 4x4 Board

hello
i am going to look at a 12ht this week end and i would like to know what would be considered as acceptable compression for one with 263000K's on it???
how do i perform the compression test ???
and what oil pressure should it have???

and if anyone can think of anything specific i should look for ???

any help will be greatly appreciated
cheers

Oil pressure 85psi at 3000rpm nominal.

Nominal Compression 427psi 2942kPa
Minimum Compression 284psi 1961kPa
Max Difference Between Cylinders 28psi 196kPa

Look for rust, particularly around roof line

Look for oil leaks (rear main, front main)

Look for oil leaks around the hubs, diff oil will run down the inside of the tyre.

look for oil leaks around the pinion front and rear.