Engine mount bushing compression

[Birdseyeview]

My series 6 with the 912 ULS has the same angled configuration engine mount and bushings as the series 5 and I can't seem to find a good description in the build manual of how much to tighten the 4 bolts that put compression on the rubber bushing stack. I believe the mount configuration is called a "Dynaflow" or something similar, so its not a "ring" mount. Do I tighten the nuts down so that it all compresses down onto the ends of the internal steel mounting bushing or just enough to allow the cotter pins to engage the castle nut (as shown in my picture)? When I tried to tighten the castle nut down until it seemed to be stopped by the ends of the internal steel mounting bushing it was nearly beyond the reach of the cotter pin hole in the bolt. I appreciate any insight gained from experience.

[Dusty]

This seems to be similar to the model 4 mount ,there was a service bulletin? Regarding the crush sleeve length.
The nut is tightened to torque on the sleeve .

[Birdseyeview]

Dusty, Thanks for the input which was just what I needed to get past this issue. I found service bulletin #54A and luckily my kit was shipped with the proper length bushing and I just need to add a few washers under the castle nuts.