Bruce asks:

<<  Are you sure these things wont fret and pull through the fiberglass without some kind of tinnerman washer under the stud nut? >>>

Yes Bruce, I AM sure. On my IV-P, I used 28 Livelocks to hold on the cowling. On each side there are two between the prop and inlet (see picture), four on the upper cowl to fuselage above the upper / lower joint, 4 on the lower cowl  to fuselage below the joint, one on the lower cowl just inboard of the exhaust and three along the gear door. The cowling is fiberglass and there are no washers. I used a hinge to fasten the upper and lower cowlings and I brazed a socket head cap screw to the end of the hinge pin so that the same hex wrench that removes the Livelocks removes the hinge pin. There is a joggle lip across the top of the cowling , eliminating the fasteners in that area.

My plane first flew in 1995 and has over 1,000 hours of flight time. It takes less than a minute to remove the cowling. The cowling has been on and off hundreds of times and ALL the Livelocks are the original  parts. 

Screws and nut plates do not have the same shear capacity as the Livelocks are effectively 0.250" fasteners. Nut plates are not intended for hundreds of install / remove cycles and loose their locking capacity over time. Philips screw slots "cam out" and strip.

If you are still unsure, just buy one pair to play with. Caution. Don't buy one if you can't afford 28. You WILL want them.

Regards
Brent Regan