Front caliper pistons simply push back. Hold one in place with a suitable tool, to stop it pushing back out whilst you push the other one in. Nice and easy mate.
Sensors will depend on your car, I think that most cars will have had these connectors removed, so simply use a sharp chisel to cut the lead away from the new pads.
Worth having a look first tho, to make sure that the connector has been cut back. If so, you should see the remainder of the cable cut back to the arch liner( cut end should be just behind the strut somewhere), unless they have been completely removed.
Not a problem to run with these disconected. Just means you need to keep an eye on your pad wear from time to time.
Hope this helps.
Iain.
