I fixed it so it would compile but you have some "clean up" work to do. I am not sure what you really want to do.
You error was in the lines:
if (MFI_M1 > 80){ MFI_M1 = "-"; color_M1 = Green;}
MFI_M1 is a double and you were assigning a string to it. I changed it to"
if (MFI_M1 > 80){ MFI_StrM1 = "-"; color_M1 = Green;}
To fix the error.
Do you have the ORIGINAL SIGNAL BAR source code?
If so, please email a copy to scottybrickman at gmail dot com.
Thanks.