Just did my door check straps, its like a new door
 

Highly recommend doing your door check straps.

I did the front 2 from the directions under D.I.Y. on my W201.

engatworks' instructions work to the tee!!!

I highly recommend it for anyone look to keep those doors stiff!!!

My car has 152 000kms on it now and I noticed a huge improvement!!!

One piece of advice, when you are hammering out the lock pin on the check strap that attaches to the inner door seal, use cardboard up against the sill and wedge it between the pin and the sill so you can save you paint from getting scratched from the hammer....

Take care guys....

Now to figure out the rattle in the engine bay....

I have replaced many door check straps. One thing I do is to take about a two inch piece of racers tape double thickness and stick it right under the pin. This works very well to protect the paint.