No. This is a nightmare.
Firstly an i7 quad core is not an upgrade. The 820-2914 board will die on you for no reason. Combine a sandy bridge quad core processor with a terrible AMD GPU and you have a toaster that will continuously die on you, and Apple's extended warranty program on that only lasts to beginning of next year. That machine was recently put into an extended service program by Apple after over 20,000 signatures on a petition and a class action lawsuit. You do not want to own that machine!
This leaves you with dual core machine from 2010, which is 820-2849. This board is slower, but at least will last you a while. However, wifi/webcam connectors are different, and probably more, which means replacing the display assembly, top case, and a bunch of other stuff. At this point when you consider all the parts cost, it makes more sense to just buy a 2010 A1297 machine if that is what you really want.