nc_lx5.0

Got a question about these kits maybe someone can help me. Ok I know there are two different kits, 2005-2009 and one for 2010. The pump will work in either year models. The only thing they state is that the 2010 kit will show incorrect fuel reading in the 2005-2009 cars.?? I have the 2010 kit which I was able to get really cheap, I couldn't pass it up. Does anyone know how off the gauge will be and is there a way to get it to read correctly? Thanks for the help!

Edit: I just read on modded mustang where a guy had the opposite problem I did. He had a 2010 and Installed the 2005-2009 kit. I haven't been a me to talk to him but he said stated in the thread that the frpp pumps were showing totally opposite resistant reading versus his factory sending unit. He said he cut a wire on the frpp pump and soldered it on top. Not sure what he means by that. I'm not the best electrical guy so if anyone thinks they might take a swing at this let me know. I don't mind paying for help!