changing rear brake pads on my 2.6 cabriolet, ive got the caliper off and the old pads out but cant manage to get the piston back so i can fit the new pads. i would be grateful for any help thanks.

C Clamp usually works for me.

you'll need a rather large hex key ... do to the fact that the e brake works off the rear calipers .. the pistons actually scruew back in ... look carefully on top of the piston there might be a heat shield of sots there or lots of dirt thats preventing you from seeing the hex slot on top of the piston

I use regular clamp. I think I used 2" clamp but bigger be better. also you can put the old pads back in, and use a crow bar or large screw driver to pull pads apart. Also the E brake might give you problems, so just unplug it as well. I think lust pull the leaver with a screw driver and pull the cable out. it just has to be not in contact.