Clutch and Brake master cylinder replacement

[Andyp_67E]

I am going to change both the clutch and brake master cylinders as clutch cylinder is leaking and brakes pedal always sticks or greater resistance on pressing after storage then the pedal gives and then back to normal, also time for a fluid replacement.
Not bought the parts yet but replacement straight forward to source from usual suspects, anything else i need to buy at the same time.
I have seen mentions of removing the whole pedal box to do this job, is this easier?
Any thoughts before i start.

[MSM]

Andy

Definitely remove pedal box otherwise you are on your back with crud falling in your face trying to remove split pins.

[abowie]

As above, remove the pedal box and do all the assembly on the bench.

Disassemble the reaction valve at the front of the brake master, remove the tiny piston and clean and then thoroughly grease it before reinstallation.