Volvo C70 mk 2 2006 - changing rear brake pads.

The last time I changed brake pads was about 40 years ago on my MGB, and
things seem more complicated now.

I've got the wheel and caliper off, but I apparently need a brake
caliper rewind tool - on order, and I'll collect it tomorrow.

Can folks please confirm that I can't just push the caliper back with a
G clamp?

Also, I tried putting fine nosed pliers in the two holes and turning
those, but there's absolutely no movement whatsoever. Is it really meant
to be that hard to turn?

Finally, I released the handbrake before starting. Is there an
adjustment on the handbrake that I have to slacken off before I retract
the caliper? I'm reluctant to pull the gaiter off from the handbrake
because it's a bit elderly and looks like it will split. So, I won't try
unless I have to.

Thanks.