Before you start loosen off the central adjuster (the bit both brake lines connect to in the middle of the bus) and note which way round is is fitted - they are handed.
Its a rear wheels and drums off so MAKE SURE YOUR WORKING SAFELY when under the van...2 ton + gravity means these things fall fast and heavy if it goes south! - your probably going to have fun getting the drums off if they are lipped
I would (as I have always done on any vehicle) get a grinder with a sanding disk on and remove the lip.
I also always take the self adjusters apart apply some copper grease then rebuild them to as the bind up on all vehicles - they only ever move a very small amount over a long time hence them seizing up.
Starting at the back of the van and working forwards....once you have both cables replaced take a drum off then adjust the self adjuster so there is a smidgen or drag on the drum, do the other side then adjust the central adjuster back up and pull the hand brake on/off a few times then re-adjust the auto adjusters
Its an easy enough job todo just takes a little while and involves getting grubby and rummaging round under the bus
