[HO455]

To remove the hose cut it off just above the fitting and use a 6 point deep well socket to loosen the fitting. If it starts to twist off or strip you may have to replace the slave cylinder. Or unbolt it from the backing plate, disassemble the cylinder and after the rubber components have been removed use some soft heat to break up the corrosion in the threads.

If there was as much crud in the fluid as I am imagining from your description, at the very least you will need to remove the slave cylinders, disassemble them and clean them with fresh brake fluid. The same for the master cylinder. Then when they are off you should blow all the lines out with air. For this to work well the lines will need to be disconnected from the proportioning block and it blown out separately. The lines and proportioning block should have air blown through in both directions.
Once this is done then you can reassemble the master cylinder and proportioning block to the lines. And then put fluid in the master cylinder so you can pump fluid through the lines to further flush crud out. This is very messy but if you get 3 caps to put on the lines you can do them one at a time with a hose to catch the dirty fluid. If you put the slave cylinders on before this step you will push more crud in you freshly cleaned slave cylinders. Once you get clean fluid from all the lines you can install your new hoses and hook them to the slave cylinders and then bleed your brakes.
Now this is a fair amount of work with no real guaranty that you won't have further problems. Instead of doing this on my Burban I made replacement lines out of NiCopper tubing and installed them with cleaned cylinders and calipers. No more rusted lines to crud up the fluid.
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