I would not attach it with Eternabond tape. I would look at either a different type cover or come up with some unique way to modify it so it can be installed.
Other than that and some McGiver skills and pictures I can't offer much more.
2011 351RLTS Eagle, Mor/Ryde suspension & pin box
06 F350 Lariat PSD, SRW, LB, CC, EGR delete kit, 16K DrawTite hitch, Timbrens, TST TPMS
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