M&P45 FS Technical Spec search

[RCawdor]

Greetings,

I have a M&P45 FS (4.5" barrel) and I am looking for technical specs on it; such as spring lbs. Would anyone know of a place on the web I could get this information?

Also, I have been searching but having troubles finding just a Recoil Guide Spring upgrade/replacement. I would like to go to a higher lb spring then the stock one. Would anyone have information regarding this?

Thank you for your time!

RCawdor