I have an 89 300CE (luckily, only 80K) with the 103 engine and experienced hot start problems as well. similar to your Redlava. After researching posts here, I attempted to solve it myself through the 'parts replacement process' to no avail: OVP, fuel system check valves, fuel pump relay. It appeared to be fuel pressure leakdown but the MB dealer measured it and it was stable. Still, the dealer could not diagnosis the problem.

I ended up taking it to an independant shop (Brooklyn Motoren Werke) here in southern Wisconsin and he solved it - it was the fuel injection nozzles! He claimed it was accumulated carbon build up and lots of partial throttle use that affected the spray pattern.

good luck!