My driver's side lock is a bit tight when I attempt to unlock it. I'm about to do the keyless ebay install. I'm going to buy the actuator separately. Should I get a specific one? Are there others that are more powerful than others??

You only need a 2-wires actuator, simple one will do and they are normally pull/push quite strong. The W123 has a vacuum switch at the driver door to lock/unlock. It takes minimum force to move it. It is easy to install but you need to drill 2-3 holes to mount and align the actuator well to pull/push the switch.

If it is tight when locking/unlocking manually then it is the linkage problem. You need to fix that first.

Good luck.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

ah-kay.. thanks for the info.