You may want to consider a few other things.

Your car has several rather expensive common failure items. They are the head gasket, (as you already know) engine wire harness, throttle actuator wire harness, and air conditioning evaporator. Approximate repair costs are $2,000, $1,500, $800, $2500 respectively. If you have the original engine wire harness, it is very likely that you will have to replace it after doing the head gasket. Removing the head requires that the harness be disconnected/reconnected. The resulting movement will cause shorts in the wire harness. The throttle actuator harness will not be affected when the head gasket is replaced, but if it is original, it will likely cause problems in the future. As for the air conditioning evaporator, if it is original, it will likely leak at some time in the not to distant future. Over the past two years or so, I have probably looked at a dozen 93-95 model 124 MB's. The failure rate for the original ac evaporators was in the 75% range.......

I'm not trying to scare you with this, I have three model 124's and they are all excellent cars and a joy to drive. I have dealt with most of the above items on all three cars. In my case it's been worth it, but cars are my hobby, and I do all my own work. Your situation may be different.

J. M. van Swaay