after 15 yrs I decided to replace the nutplates[which didn't have much resistance left in them] along the firewall and nose with camlocs. turns out I could only use the original style because of the small amount of flange to fasten to. camlocs reach is sized by the 1 /32". I discovered that my fiberglass cowl [the old, original style] varied quite a bit in thickness. the seat of these camlocs are not adjustable, but the plunger 1/4 turn screw part comes in various lengths. after much messing around [I was replacing 24 nutplates] I also discovered that the one time only locking washer adds to the thickness, so your trial fits may be off. fortunate for me, Columbia Aeromotive is up the street from TTD. I made many trips. I forgot to add that the hole distance for camlocs is about a 1/2 rivet width narrower than a std nutplate. I machined an adapter drill guide to locate the camloc seat exactly where the nutplate had been so that the holes in the fiberglass cowl still aligned. so, long story long, use the adjustable ones if possible. [I didn't have the choice, no room]. if you do, first buy a set of #6 thru 10 and use these to figure the correct fastener length for each hole, then order the rest. with the flush fit camlocs, setting them in a 1/4" thin washer will perfectly replace the tinnerman washer used with the #8 screws. total cost for 24, maybe $180?