hanging out site platforms (Scripts) Whats this going to do to my rank?

Hi,
I have pretty good rank for targeted key words on a site I have but I need to change out scripts....so all my inner page urls will change.
I have to change scripts, because the one Ive been using is crap and throws alot of errors, and uses unnecessary resources in high traffic situations.
Is there a smooth way of going about this?
any suggestions would be greatly appreciated!!


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Search Engine Optimization|Web Design Orlando