Well, I went to do the caliper just now, the top 17mm bolt on the bracket needed a lot of force and hassle to come loose, when that was broken went to the bottom one and it is rounded off completely!! Quick call to Richard Henry and heading up there later to let them have a go.
It seems everything the last owner touched is either broken or bolts are seized. Luckily this is the last thing I haven't changed that he did something with, and even luckier he only had the car for 7 weeks so didn't have that much time to do much damage!!