If there is anyway to leave them on and polish in place, do that.
These can be a ball buster to get off without messing up! FORGET the urge to use pliers. I have had good luck with bumping them off with a piece of hardwood, maple or cherry work well. Make a fresh cut on a table saw so you have a good sharp edge, a 10 to 12" long 1x2 and maybe a narrower one for the curved part at the back window.
With the windows down, and from inside the car, hold the wood block squarley on the lower lip of that moulding and start from the front working aft and tap the block with a hammer and you should get it to start rolling off. It helps to have some help holding the moulding with slight tension to ease it off as you tap, and watch your paint. If you have a helper they can use a light twist to help the moulding along, It can get alittle tricky as you work the curved section. Work slow take your time.
Good luck Mike