how hard is it to replace tension pulley and idler pulley with "Likens kit"

Hello, If the factory pulleys are not bent/warped/deformed, then changing to another pulley set-up will likely not help the situation. You will first need to identify the slouching or defective pulley, solve the issue, then replace. Pulleys are easy if you have the proper tools, and impossible if you do not (on most models). Let me know if you have questions while diagnosing, otherwise, I'll leave a link to certified shops in your area. http://repairpal.com/dodge-within-10-miles-of-wilmington-north-carolina-28403