I bought a TEP Strut Brace from a member of www.bmw2002faq.com and installed it immediately. It's a big improvement over the $15 E36 strut bar that I had hastily modified to fit and was rubbing against the intake manifold. The new (used) TEP brace not only holds everything much stiffer than most bars with it's triangulated design, but it also offers the option to bolt an arm on that limits engine movement. Of course, since it was designed for an M10 and not an M42, I'll have to modify it to keep the M42 in place.
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After: