i have new discs on order and was looking at the caliper and noticed there was only 1 bolt holding it on at the bottom of the caliper, are there any more holding it on and can some one give some advice about changing them do you just take of the caliper and whip the disc off

 

There is 1 bolt at the bottom of the caliper (as you pointed out) and a pivot at the top.
To change the disc you need to remove the caliper and the carrier it bolts too.

There are 2 14mm bolts near the pivot and the caliper bolt you saw.
Take the caliper bolt out and remove the pads first.
Then remove the bolts holding the carrier to the hub and swing the assembbly out the way (don't let it hang on the hose).
You will probably have to loosen the hand brake shoes. Ther is a little rubber bung behind the back plate/hub. Pull it out and you will find a toothed wheel. Turn this (I forget which way) and it should slacken the hand brake shoes.
The disc should now fall off, if not a tap with a hammer will do it

Clean all the mating sufaces on the hub and remove any protective oil film from the new disc (not forgetting the hand brake drum inside) before fitting.
Once fitted re tighten the hand brake shoes and rplace the caliper and pads

Check the pedal before the test drive!!!!!! Pump it a couple of time to make sure the pedal is there

 

cheers dyney most helpful