Not as far as I've ever seen back in the 70's, but some owners put them in there themselves (& maybe some dealers) to reduce paint wear & the rubber squeaking in the floor on rougher roads.
I never glued my added ones in, but just laid some scrap felt under the tire on each bearing point (3-4 pieces).
It was a trick my mechanic taught me, & he was the Circle Porsche+Audi dealer in Long Beach CA's 914 specialist, before he started his own shop in `72, & he said that was their "special secret dealer fix" for the squeaking (imagine it said in his thick Austrian accent).
PS - that looks like an excellent 914 too!
Cheers!
Tom
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