I have a ec250 2018 and a ec300 2015. I want to change cylinder on the ec250 to a 300cc I have looked at the part lists and it has different part nr 2015-2018. But there are some s3 300cc cylinders on ebay and they claim that it fits 2000-2019. So are they any differences between the cylinders over the years or does a 2015 ec300 cylinder fit a 2018 ec250?