That's a shame about the bulbs, although the Athearn bulbs are always lambasted by everyone, its a shame you blew them! Wish you had of asked as I'd could have given you a heads up here!!
Mind you, Athearn bulbs being what they are, they seldom last more than a few weeks anycase.
If you want to replace them, ive a fair few that Ive removed for LED's myself. All Il ask if you want them is the cost of postage for half a dozen of them.
For an ESU newbi like myself, that was an informative video!
Its interesting about the 'bridgeable' pads for 12V bulbs or LED's as NCE boards use the same thing on some of their DCC decoders! Its certainly a useful feature!
You may need to check the output voltage on those light pads as with the resistors in use for 1.5 volt bulbs, I don't think that will be enough for a LED??!!
Ive ended up bridging the pads (like you already done) and used my own 750 OHM resistor for each LED.