[W126 Coupe] running 16 amps in fuse 9?

[Shayegan, Richard]

My fuse 9 has an 8 amp fuse in it because I have neither heated nor
orthopedic seats. I see that if I had those it would have had a 16 amp
in it. My question is, is the wiring the same no matter which set up you
have? I just realized my new head unit will be using 9 amps. I'm going
to try it with the 8 amp first, but if I keep blowing them, I want to
know if I can safely stick a 16 in there. Anybody know if the dealer has
these types of fuses in amp ratings other than 8, 16, and 25, i.e. is
there like a 10 amp?
Thanks,
Richard