I cleaned out the EGR tube without disconnecting anything except the EGR valve itself and the tube at the intake manifold.

1] Where the tube goes into the intake manifold, a 10mm wrench is the only tool for the rear bolt and a 1/4" drive socket can be used on the front bolt. The bolts are about 2cm long, so it takes a little patience usng the wrench. Easiest way is from under the car. The little pia was keeping the gasket in place when reattaching.

2] To prevent the spedo cable from wrapping around itself, I fed it though a 1/4" plastic tube, inserted one end in the EGR tube and occassionally split the plastic tube as the cable fed into the tube.

Someone else used a "bicycle shifter cable" and noted most of the crud is at the intake manifold end of the tube.

Bob