I've got some rust on sticking issues on the front calipers. I have the pistons now both pushed out facing each other after putting a compressor on them. They are still removable. Do I b=need to take the caliper apart (split in half) to remove and clean th episton and barrel??

No. If the pistons are out enough just remove but don't split calipers. Don't use anything on the pistons that would scratch the cylindrical surfaces.

I've had good luck spraying the exposed portions with PB blaster and pushing them back in then using the air and a block of wood to pop them back out. Sometimes it takes a couple back and forth motions to get them all the way popped out. Definitely use a piece of wood for the piston to land on when it pops out and keep your fingers clear.