The SLI Bridge I posted looks like it would fit for both 25mm, and 37mm...
At its shortest (18.0mm), it barely fits for a 25mm fan (18.4mm spacing), and at its longest (30.0mm), it could theoretically fit a 37mm fan (30.4mm spacing) with only a .4mm washer on one side of the fitting.
Sounds to me like there is a market for a flexible D-Plug design... If this is even truly an issue, then all it would take on Swiftech's part, is 'binning' their radiators for the "Premium Stack" model... make sure the radiators they sell in that kit meet the tolerances required to square up that connector.
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