[Chris_]

Couldn't tell you in any major technical detail. but.

The four bolts hold it to the rear beam, the rear beam attaches to the body with some quite sturdy bushes, one at each end.
Although these are strong i think they would be wear out a lot quicker if it wasn't for the 'ear' which i have always just presumed is the main torque bearing structure. But actually looking at it a little closer, i reckon you might get away with just mounting it with the four bolts.
They are spread across a decent length, and are at two different seperation distances. I reckon it could take the loading ok.

Need someone clever to look at it i reckon.

Chris