Time to add more to this
Real oem showed me that e92 have an extra braces:
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These braces look like 1/4 of the convertible e93 /e88 /z4 braces( Specific to engine clearance lower into the engibe. So check first)
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Since the convertible braces need a sub frame swap or a small custom mount, these are the next best thing. They attach from fender/strut area to the Crumple arms, they may need a bolt: 07119905147 and nut for the lower end 07119904670
The Driver side/Left may need a bolt in the bottom instead of a nut, my e82 doest have it...
EDIT:
Appears there is a bracket for the sub frame available for the early e93 that allows mounting of the V brace !!!!!
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One has to use 2007 spec V rod braces - engine specific, pls check
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V long body
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Bolts ( not sure of quantities, pronb 2 each
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Lock plate - not sure of use ?
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LCI e93 /135i e88 front subfraame what it lookslike: