I have a few questions regarding my Lexus IS300 F Sport audio system. To preface, I do NOT have the Mark Levenstein audio package. With that being said I do not know much about what speakers are in my 2016 Lexus IS. I know subjectively they sound pretty good. However, I have a set of 4 Alpine Speakers and 2 Alpine tweeters from my old vehicle. I have (2) SPS-610's, (2) SPS-610C's, and (2) SS-10TW tweeters. With that being said here are my two questions:

1) Would the alpine speakers that I mentioned above be an upgrade worth installing, clipping the oem speaker lines and installing the alpine speakers?

2) I know when I ran the alpine speakers in my old ****box I needed an additional internal amp. However, I assume that the OEM system has an internal amp already. Is this a fair assumption? That way if I do install the alpine speakers I wont need an internal amplifier?

Sidenote: I have an old kicker 10" sub that I may or may not install... if I do, I have an amp that I bought for that.