you can swap hubs around but then you need to start re-drilling discs. Not 100% that 4 stud ones will go in 5 stud bearing housings, afaik its only been done the other way (5stud hub to 4 stud bearing carrier)
if you were to swap the entire bearing carrier back to a 4 stud item, you also need to swap the wishbones, anti-roll bars and drive shaftt/outer c/vs. reason is the 4 and 5 stud bearing carrier lower balljoint is offset differently, so fitting with 5 stud wishbones would result in wheel not being centred in the arch.
Then if you change wishbones you also have to change the anti roll bar as the pickup point is different 4-5stud
