The subject of fitting wheels and tires to an E28 is actually less complicated than it often seems to be, and The BMW E28 Wheel and Tire Tutorial should clear up almost any question you might have about it.
TEMPORARY LOCATION:
IMPORTANT -- YOU NEED TO DOWNLOAD THESE AND OPEN ON YOUR COMPUTER, NOT ATTEMPT TO UTILIZE THEM WITHIN DROPBOX:
https://www.dropbox.com/s/rcew5enww111e ... .html?dl=0
https://www.dropbox.com/scl/fi/j39jfq2m ... 85dbu&dl=0