Future BMW Wheel Research
In the future if you want to look a wheel up this catalog can be helpful although sometimes it take a while as there are so many wheels.
http://felgenkatalog.auto-treff.com/
Boring the Hubs
As far as the wheel boring goes basically you are making the hole larger to accommodate the larger e39 hub. I have heard of people doing it themselves at home, but since BMW wheels are designed to be hub centric it is probably better left to a machine shop. They will be able to enlarge the hole and keep it centered so the wheel will then center properly on the hub. Although I think there is a minority out there who say that the whee bolts will center the wheel, but I don't think its worth it. It seems people have paid from $20 to $60 per wheel ot have them bored.
Other options
- Aadapter spacers ARD and H&R make them (may not work with the offset of those wheels you are interested in as the offset is already pretty low)
- Change your current e39 hubs to e60 hubs and you can run the standard 72.56mm BMW wheels, provided the offsets work our course.
Check out this thread it may be helpful. It mentions the cost of machining, doing the work yourself, spacer adapters and changing e39 hubs to e60 hubs.
http://www.bimmerfest.com/forums/showthread.php?t=614946&highlight=machine+wheel+cost
Offset
Also keep in mind offset ranges as well if you have not already. This post may be helpful.
http://www.bimmerfest.com/forums/showpost.php?p=3587357&postcount=3
I'm not 100% sure,but it looks like those wheels you want should not be an issue.