VictorYlap

I have recently managed to score a Santana tandem off craigslist that fits both me and my stocker (most frames on the used market are far too large). It is probably from 1988-1990, made from Columbus tubing, with Suntour XCE indexed downtube shifters, 48-spoke Suzue hubs, etc, everything in great condition, even the indexed shifting worked perfectly after sitting in the seller's garage for who knows how long. Not sure about the particular model - Arriva, perhaps? I've sent an email to Santana but have yet to hear back from them.
I'm going to refrain from any upgrades (except for the saddles and pedals) until the drivetrain starts to wear off, so I have just disassembled, lubed and re-assembled everything.

Now, the question is if there is a manufacturer-intended way to mount the mudguards and the racks. I mean, this is clearly not a racing bike, so they should have figured that the riders would like to put on some extra gear.

Of course there are always clamps or ziptie-mounted contraptions like SKS Raceblade, which I have on my road bike and really like, but they will look totally out of place on a vintage steel bike.
There are eyelets near the rear wheel dropouts, and there is a threaded hole on the back of the fork, but that's it. No mount on seatstays, near brakes or at the bottom bracket. I could use a set of QR-to-eyelets adapters (like from Velo Orange or Axiom) and get the front mudguard properly mounted, but have no idea what to do with the rear one.

As for the rack, I think there used to be eyelet-and-cantilever-posts MTB racks which can be used in the rear, but I'm more interested in the front rack since the rear wheel is already overloaded on a tandem. One custom rack builder I've contacted suggested drilling the front fork (currently the threaded hole in the back of the fork doesn't go all the way through), but I'm not sure if it's a good idea.

Turns out I cannot enclose images or post URLs so far. Hopefully I will be able somewhere later in this thread.