I had no trouble with the bolts dropping on our 190E. I used an allen end for a 1/2" socket set, a 6" extension, and a long breaker handle. The bolts loosened easily, and stayed captive on the allen head as I spun them the rest of the way out with the extension.

The hairy one was the upper hex head bolt on the mount - driver's side. No way to get any torque on that until I removed the FI system from the manifold and used a looong extension. Ease may vary with other models.

Steve