[Mike8519]

Well apparently the only robust attachment system allowed is a bolt with a tee put into the plywood as per figure 8-1. Even though parts G and H of R08 seems to imply there is a possibility of other robust fasteners. The note in the primary paragraph of R08 ("To achieve this, BUMPERS must be constructed as described below and illustrated in Figure 8 – 1") defeats the later subsections of the rule.