I always encourage electric bassists to take up the upright, just because it's so much fun.
http://youtu.be/2SriEOjsDCo See what I mean?
Bass Guitar To Upright Bass: The Top Ten Mistakes Migrating Players Make. Greg, I couldn't be more impressed by your monumental achievement. I mean that right down to my core. Consider this a standing ovation (yeah, I'm sitting down, but you know what I mean).
I know how insanely difficult it is to seat an adjustable bass bridge, correctly as only an inept buffoon who has learned a very valuable (as in; expensive) lesson from hubris and over exuberance can attest.
Brunhilde came with a warped fixed bridge, and I was all hot to get a David Gage Realist pickup so I picked up an adjustable bridge for her. Special order from Germany, too. Woo hoo!
It's interesting that you used the word yaw because that's the perfect word to describe one of the three most important vectors to contend with when you're trying to sand the bridge's feet to conform to two separate compound angles, so that the bridge stands at a perfect right angle to a surprisingly flexible top (or table) that slopes in approximately umpteen directions at once.
It was the adjustable feet that doomed my first attempt. I smeared a dab of lipstick on the bottoms of the feet and taped sandpaper face-up on the top, measuring and measuring again and finally, C-clamping a long - straight - length of 1x1 molding to the end of the fingerboard for reference. (Like your homemade pencil gizmo.) That's where those adjustable feet threw me off.
I got the worst thumb-cramps I've ever had from gripping those feet between my thumbs and index fingers, like I was trying to crack walnuts, and slowly dragging them back and forth, back and forth, back and forth ... Meanwhile, every time I paused and looked at the bottoms, a different part of the base was getting sanded off than I was expecting. Every time. I couldn't for the life of me figure out what was going on. I'd get closer and closer, then it would go wonky on me.
Finally I realized that I should have placed the sound post first, because every time I gripped the crap out of those adjustable feet and bore down with extra determination, the table flexed. The more I tried to work on a certain area, the farther off it went. When I wrestled the sound post into place, it was too far gone and I think I may have sustained permanent damage from kicking myself in the ass.
That's also when I found out that you can't buy the little feet separately, and of course I was too dumb to make my own.
I took her to John Stewart in Massachusetts with my tail tucked between my legs (makes it difficult to walk, especially if you're prone to tail-wagging, like me) and vowed to never mess with classical instruments again.
Good thing I did, too, because he told me that even though she's a hundred years old (still has her curves, though) nobody had ever set her up properly. The nut was too high, the soundpost had been turned around to some degree by some nimrod (raises hand) who was unaware that the end was seated to exactly conform with one particular angle, so that only about 10% or so was contacting the back ...
My god, what a difference. There's an unbelievable amount of skill and knowledge involved in that stuff. And I had been playing upright since I had to stand on tiptoe to reach an F but had no idea that there was so much involved.
I always say that because I started playing upright in school orchestras, by the time I figured out that I was too dumb to play it, I was already pretty good at it.
Sonicus, the soundpost is really there for playing the bass with a bow (arco). There is no electric bass equivalent, because the bow literally excites the whole instrument (your left hand can go numb from the vibrations). It's the coolest feeling ever, and like the video of slapping I posted at the beginning of this seemingly never-ending rant demonstrates, it's surprisingly easy to do.
Besides, the string bass is the most versatile orchestral instrument, by far. It's used in more types of music than any other instrument. It's changed very little in over three hundred years, and so it's our legacy as cool guys (that 350 year old bass I posted pictures of was hauled around Venice in gondolas, by guys exactly like us).
My only other advice is to get lessons, because we hold our left hand differently so it's a lot less stressful on your fingers (especially the way we balance on our left thumb). Get it set up by a pro and arguably it'll be as easy to play as your Alembic, with slinkier strings.
And once you get past the part of using a bow where it sounds like a walrus being tortured, you'll discover this incredibly powerful resonance and singing qualities that'll rock your world. Words can't describe it (that's never stopped me from shoveling as many as I can, though).
