Well my concern is plumbing it up to a 5.0's power steering pump
Well the 2000 mustang v8 power steering pump interchanges with the 1996 mustang v8 power steering pump according to car-part's interchange. The 2000 has hydroboost and the 1996 does not.
I know I can run a 1996 power steering rack in a fox with a fox 5.0 P/S pump.
So if a fox 5.0 pump can run a 1996 rack. And the 1996 pump is the same as the 2000 pump that runs hydroboost, I see no reason why a 5.0 pump can't also run hydroboost.
Whatever needs to be done with the lines, in order to do the SN95 power steering rack swap, would also need to be done to run that pressure line to the hydroboost. From there, you would simply use the factory line to go from a 2000 hydroboost to the rack. The 1996 and 2000 call for the same rack & pinion.
The only snag may be if you're using a fox rack, in which you need to know if that factory line from the 2000 hydroboost to the rack will fit. I would go to a parts counter and have them bring a rack for your car, with that 2000 booster-to-rack power line and see if it fits. You may need to get an adapter fitting.
The return lines for both can simply be T'd together with standard fittings and hose clamps, because it's not under pressure.