Will the logic board from a 13' 2012 MacBook work in an early 2011

From what research on compatibility I did, it looks like it will work, but you probably also want the newer WiFi card to get BT 4.0 out of the system. There isn’t anything specific on chassis catches, so you may want to check the board layout yourself against a 2012 board to confirm all of the holes line up 100%. It looks like the card iFixit sells is the BT4 one for both machines.

You will also need to replace the heatsink as the 2011 one won’t carry over to the 2012 board. Build this into your estimate at a averaged price since it may not be as cheap as you want it to be.

When I got mine (Late ‘11 with livable cosmetic issues at a discount), I was told that there is no real performance gains with the 2012 i5, so you probably want an i7 board to make the bump meaningful - unless the client just wants native Mojave/Catalina support.

In addition to that, I looked at the boards for the 2012 and 2011 and the holes match up.