1970 R/T hood trim attach fasteners

[femtnmax]

The fasteners I've found to attach the leading edge trim piece are either spring loaded studs with stamped nuts, or bolts and common threaded nuts which hold plastic pieces that the trim snaps onto.   
The spring loaded seems like it would "positively" hold the trim on, whereas the plastic clips rely on correct shape/size of the clip and the aluminum trim piece. 
Which is correct OEM style?   ...and which actually holds the trim on the best?

[MEK-Dangerfield]

The fasteners are the spring loaded type as you mentioned first. There are a couple of places along the back of the trim that have a slightly larger opening that you use to slide these clips on. Then you slide the clip to it's correct location. There should also be a sponge-like material in the groove on the back of the trim that would hold the clips in place.

[Chryco Psycho]

they typically use a threaded nut with a lock washer attached at least in early 70 models