PS Greg,
Just to be clear, I was answering based on your OP statement:
"Here's the question, from a concours judging perspective, how "incorrect" is the non US Karlsruhe radio?"The NOS Euro Blaupunkt is not incorrect per se, but it could be challenged by a competitor in a PCA Parade under their rules, as not being original or correct for a USA delivered 914, or if the COA says another radio was installed at the factory, or a dealer's invoice to the contrary (if you have that documentation).
It's my understanding that challenges like that are infrequent at Parade, but it can happen. As I said in my prior post, there have been other 914s which won their Class/Division at Parade with other & far more extensive non-original items in recent years, from what I can see just looking at the pix from Parade. So I don't know how much of a concern it would be for you - assuming you plan to show at Parade.
For me, the bigger question would be usability in the car here in the USA, & whether that set you show will pick up our stations, regardless of whether the dial & buttons are shown in Euro or USA standards. The dial looks like they may be the same frequencies as in the USA, but I don't know if your Euro Bands Blau will pull in the USA AM &/or FM stations, as I don't know the difference with their bands, so try it out to see what it gets.
The good thing about the Euro Blau is that it's dead perfect NOS & looks great!
FYI - Jeff Bowlsby's 914 site lists the factory radio options in the chart by MY at the first link below, & the range of dealer & factory radios are about 2/3's down at the 2nd link (my Moto AM/FM/8-Track is the VW 4412 on the list of pix linked there).
http://bowlsby.net/914/Classic/OpEq.htmhttp://bowlsby.net/914/Classic/Accessories.htmAs noted above by myself & others, unless you're trying to stick with a radio option listed on your 74's COA or Kardex, you can put in any period correct radio to "look" 74-ish.
For non-period but Porsche-made/sold "Porsche Classics" division radio options, there is also the Porsche sold classic radio with Nav (see link below, Suncoast Porsche & your local dealer can probably get it too), which would pass for anything in Concours at PCA Regions/Zones, but would have the same cautions which I mentioned above for Parade &/or non-PCA CdE - depending upon their individual rules.
http://www.suncoastparts.com/product/SKUCLASSIC.htmlIf you plan on both pleasure driving & CdE showing, you could also just use your NOS Euro Blau for show, & also get a good quality modern Sony/JVC/Kenwood/etc. with Bluetooth, Aux/iPhone/Android/Aux & all the bells-&-whistles to use on a daily/weekend basis.
That Woody's Customs store also sells a pair of flat speakers to get to 4 total without hacking door cards/etc., which you can set under or behind the seats in a 914, & run the wires under the carpet sections to the radio (for Concours judging I'd recco removing at least the speakers & tuck the wiring under carpets if you go this route.
They're not hard to change-out if the original wiring is maintained, & the new style is installed using an adapter pig-tail, rather than the typical Audio shop cut-n-splice hack jobs.
The choice is yours.
Also FYI - here is a pic of my Motorola set added by the OO at the dealer, which needs a good detailing before I put it back in. It has the correct original plastic basketweave texture face plate with the half-circle notch for the glovebox key/lock-set, correct knobs to match the dash with the silver tabs adjusting L-to-R Speakers & Bass-to-Treble (don't recall which side is which offhand now), M/S is Mono/Stereo selector with the singe amber light to above to indicate stereo, & the 4 amber lights are for the track indication on 8-Track tapes with the dial face hinged to insert the tape cassette-box.
Cheers!
Tom
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