I'm having the 2003 stereo unit problem where the screen blanks out and buttons do not work and the AC goes on auto AC blasting....

It seems specific to 2003 models, instead of guessing if it's the HU or circut board i'm looking to replace the whole thing...... I've found a decently price 2004 full stereo unit but I am unsure if I can just swap it in.........

thanks