IronRidge UFO and REC315TP2M . . . compatible?

Inertiaman

This is perhaps a tedious, detailed question for a first post, but here goes . . .

I've been going through a tentative racking system design for a modest ~4kW system for my home in Tucson.  When I look at REC's installation requirements ( https://www.solaris-shop.com/content/REC%20TwinPeak%20Series%20Installation%20Guide.pdf ) they very clearly specify a minimum clamp length of 40mm (see page 6 in document).

The IronRidge UFO mounting bolt/clamp uses a circular washer as the clamp head, with a diameter of 1.12" (~=28mm).  So the effective clamp length of the washer is only about 23mm (since the panel edge is offset from the center of the washer, you don't get all 28mm overlapping the panel frame).  Obviously 23mm is << 40mm, so it would seem these are incompatible.

But in their roof mount manual, IronRidge specifically denotes this REC panel in the module compatibility list.  

Shall I ignore this as a tedious anecdote, and proceed w/ an IronRidge racking system?  Or should I take these documents at their word, and conclude that I cannot use IronRidge w/ this REC panel (and *many* other REC panels governed by same/similar install specs)??

Given how common both REC and IronRidge are, its surprising to me that the specs don't reconcile.  I called IronRidge and they basically said "its compatible".  Haven't called REC yet.

I should also note than IronRidge doesn't offer any alternative "caps" for the UFO assembly, or any alternatives other than the UFO for mid-clamps, so that's not a path to consider.