yeah sounds best mate, better safe than sorry.
i would do the master cylinder too, plus change the rears, even if you stick drums on the rs/xr drums are much bigger.

things you will wanna change would be, master cylinder, calipers, disc, pressure reduing valve, drums

the pressure reducing valve in bolted the int passanger side inner wing, yours being a 1.1 may not have one, you may have the small ones that are screwed on the master cylinder just before the brake pipe, if you have a look in the haynes manual you will see what i mean.
best have a read up on the breaking system part mate just for a better under standing of whats what and whats where.....if that makes sense,