Don,
I agree with the coolant draining - not much, just enough to remove the cross-over pipe, as the oil filter housing needs to come off to change that low oil pressure SOB. 3-4 bolts and the housing comes right off, no big deal.
The oil cooler lines...may not have to come off, tho I did remove them too - perhaps I could have done it w/o removing the lines? (You'll have to see and get back to us!

)
Jerry has a new oil flter housing gasket, if you need one, or if the gasket is intact, a smear of the Permatex (powder blue color) RTV will do the sealing, after getting the housing and the gasket surface clean and dry.
P.