Scott,
shame you missed the 400 set, they had some of the rubber + mounting brackets. in order to use the stainless ones, there are additive costs. you need all of the mounting hardware, you need all of the rubber, you need the extrusions to mount the rubber to (and have to drill and mount those pieces). you will probably have another 800 to 1000 bucks in addition to the bumpers. but once done, you have nice + new stainless bumpers ... compared to chrome. you can still buy the brackets new from BMW. you can buy all new mounting bolts from W+N for a reasonable price. you can buy new rubber for the bumpers + front overriders / rear underriders from BMW or W+N. as far as the extrusions to mount the rubber to the linear parts of the bumper - you have 2 choices - buy regular steel pieces from BMW or buy stainless ones from your best buddy in Colorado. (tongue planted firmly in cheek).
glad you kept your coupe
scott