I just ordered a Caliber X-Change Kit to convert my P226 from 40 to 9mm. The original pistol is 10 years old (recently bought at Academy sports used service pistol for under $500), what springs etc do I need to change? Also, should I use the 9mm or 40 springs since this is originally a 40, but now will run a 9mm slide barrel exchange kit. I am ok with doing the work myself, have worked on Sigs and CZs quite a bit. I'm brand new to the P226 realm though. Thanks for the help!