The 2007 Bengal is not drilled for an STS. The hole would not be threaded anyway. The ones that are drilled do not have threads. It is just a straight hole with a set screw that tightens on the rod from the side of the riser.
If you want to mount an STS it would have to be a front mounted model that attaches to the stabilizer hole on the front of the riser.
Second question. The STS that Martin uses is not straight. It has a slight dog leg to it.
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