A P5 windshield will fit, so will a MSP one. The MSP one is actually lighter, and thinner I believe. If you're gonna do it, definitely replace the molding but I wouldn't advise doing it yourself. It's not an easy task. Cutting out the old windshield will result in stripping of the clear coat around the molding and you will start to accumulate all sorts of rust there.
Take it to a pro, they'll do the job right.