change heating controls

[dannyboysean]

hello to all,,,,
i own a 1995 bmw 320 convertible and want to change the heating controls from the manual round one to the push button controls like what i had in my 5 series....is this possible???
do the controls have to come out of another 320 or can they come out of a 318 316 323 325 or 328???? and does it have to be out of another convertible or can i take it out of a 3 series saloon or coupe???
if anyone knows a link with instructions and diagrammes can you please let me know...

thanks to all,
Danny