i made a set of taper pins from 3/8" carriage bolts. I used a bench grinder to taper them down.
I could never get the wings lined up perfectly enough for the bolts to go in, but I can get the wings to line up close enough so that I could get the taper pins to go in and they slide in and get the wings completely lined up.
I drive the taper pins in from forward of the spars, then I put in the bolts from aft of the spar and they drive out the taper pins.
Sonex has recommended trailer hitch pins instead of the bolts. That's what I use.
Check out my web page
http://www.mykitlog.com/donbowen. Look on the menu on the right of the screen called "Moving". It has all my experiences moving and assembling my Waiex and shows the taper pins.
Best of luck with your Sonex.
Don Bowen
Viking Waiex N49YX