Replacing the cam bearings

Lots of conflicting search results regarding changing the Rover V8 (serp) cam bearings. Is it possible to do this with the engine in? Also, from what I understand you press the old bearings out..how do you do this with the last/smallest bearing? Is there a plug behind the bearing to stop oil escaping onto the flywheel...this would seem to be in the way when pressing the bearing out?

I think I am going to do the FI build in two phases. Car currently has abt 45000km, and has a number of engine mods which produce good dyno'd power so I have no reason to doubt the engine and the spark plug colour is good.. During the cam replacement I'll check the cam bearings, compression and general condition. I have already roller rockers so that part should be fine. After reassembly I'll baseline the power again, then install the s/c. Not too concerned about the s/c install nor tune as I am already running a FI map with larger injectors so the only untested part is above barometric pressure..main concerns are engine cooling and charge temps.