I have managed to do it :) I moved all the required .Dll to my bin folder on the server.
I had to manually chnage:
@ Register Assembly="Telerik.ReportViewer.WebForms, Version=18.104.22.1686, Culture=neutral, PublicKeyToken=a9d7983dfcc261be" Namespace="Telerik.ReportViewer.WebForms" TagPrefix="telerik"
at the top of my pages that uses Telerik. I dont know why they were not updated with theUpgrade Wizard.
Thank you so much :) you rock.