e36 to e46 conversion

Dear viewers,
can anyone tell me what are the major differences in the e36 and e46 and if it is also possible to custom 2001 m3 fenders onto an e36 model.

Like this . . http://server2.uploadit.org/files/skycityBMW-e36e46.jpg

I think you can . . but you have to do the whole front clip . . . and do some modification to it