Originally Posted by stevedask
OK so there are some differences as you can see by the pictures of the MB FOB vs the original.
There are differences in both the plastic case and the metal key part that need modifying.
The first difference and obstical is the original plastic back has a single tab for the white piece to fit over and the newone has a T shaped tab. I cut the tab with a razor knife to allow the white piece to fit properly (see pictures).
2nd issue in next post
The 2nd problem is the original plastic back has a slot cut where the transmitter fits into (little black chip that your computer recoginizes and allows your car to start). The New MB FOB doesw not have this slot in the plastic so I had to guage out the slot. I did this by heating up a sharp hole cutting drill bit to easily carve out the square I needed untill the transmitter would fit into the slot and the white piece could fit in all the way down properly.
See next post for mods required to the metal parts.