I chuckle when I recently saw 42$ for a set of washer wrenches. The modified band saw blade method has worked fine for me and skewers likewise have done the trick on bolts. Not shown is a pair of needle nose plyers with the sides ground down for use in rigging the washers on the control collumn and other hard to reach spots. What I have found helpful about building your own tools is it's an opportunity to kick around ideas and think fabrication and assembly issues through.
How folks get by without owning there own machine shop has always been a mystery to me...
That's because I didn't have the thin Avery yoke when I did the rudder. We picked up the yoke at Avery's booth at Oshkosh and those little rascals are on my todo punch list....