Replacing 2011 Dodge Avenger radiator neck. How do I disassemble and reassemble?

As far as I know that is a plastic part that 'can be replaced' provided one has the required tools and talent to do so ... However it is much more cost effective to replace the radiator itself and will certainly be a more permanent repair - the radiator has another plastic tank on the other end as well - it may also fail at any time.. A quality radiator isn't that expensive - check around - you may be surprised.