CalWB -
I don't know if you got them from PMB or Cardone/parts house or another.
If they're from Cardone - return them as incorrect for a full refund - their caliper work is crap! Then go to PMB for a proper rebuild + full restoration.
If from PMB, return them to get a correct single bleeder early caliper 70-72. IIRC the caliper bodies or something are a tad bigger & can affect fitment.
Note that the front Hubs ARE definitely different 70-72 vs 73-76 - cuz in 73 MY they introduced the self-centering "Hubcentric" front hubs with the ridge around the axle hole which then requires the later wheels with the opposing inset - early wheel p/ns: end in -00, late with -01. See the O&H Forum nailed topic on Wheels & Tires for pix of the -00 vs -01 wheels.
So if you also changed front hubs (or a PO did), then that could also be your wheel fitment issue.
With our 914s it is always best for all parts to stick with the same MY as much as possible, or at least by era (early vs. late), so that everything works together & properly as the factory intended. Yeah, you can get some to work together with some kluges & adaptations, but you're still better off with properly MY matched parts wherever possible.
PS - Note that at MY change-over they sometimes mixed prior with current MY parts to use up the parts stocks where they worked together, such as my very early Aug. 72 build 73 MY having late fronts & early rear calipers, & a few other early parts such as chrome window cranks. This was common & shows that some parts mixing can indeed be done successfully. So in my case I'll be asking Eric at PMB to just restore & return my exact calipers to avoid any issues (as well as to keep my 914 as original as possible).
And before some asshat jumps in here to say I don't know what I'm talking about, this is also the sage advice of my long time mechanic who was factory trained on 914s back in 1969!
Good Luck .... again!
Tom
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