If you want to reuse your emblems then use this (what the mfgs use) It's not as hard to trim as you might think (xacto knife)
http://solutions.3m.com/wps/portal/3...beV0141B40KNgl
Or, just pick up some of this:
http://www.autogeek.net/3m-auto-tape.html
Yeah, MB's prices on OEM badges are crazy. Not sure how good a quality the Taiwan/HK/China eBay replicas are, though.