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There are a few ways to integrate an ipod into your factory system, be that by hard wiring or FM transmitter (low quality) but as for an amp, if you keep the stock head unit you won't really be gaining anything, ford factory headunits are notorious for under powering factory systems so that it is less likely speakers will blow. The move to an aftermarket headunit will give you some gains, and I think it might be a bit much to try to amplify the stock system, just something to think about.
There are a few ways to integrate an ipod into your factory system, be that by hard wiring or FM transmitter (low quality) but as for an amp, if you keep the stock head unit you won't really be gaining anything, ford factory headunits are notorious for under powering factory systems so that it is less likely speakers will blow. The move to an aftermarket headunit will give you some gains, and I think it might be a bit much to try to amplify the stock system, just something to think about.