Parnell at 2B, Lee in LF
The ball is hit towards 2B far more than LF and the extra range means Parnell gets to alot more balls than Lee and generates a bunch of + plays. Sure, he will also collect more errors with a glove that is -5 from "average" for the position, but the net effect of getting to more balls and generating outs that would have been singles with Lee is in Parnell's favor.