I have done this, and can say I like it! I used Bud's lower stay chain plates and a teak wedge under them (clear cap rail). very very simple.
see Hawaii 2007 I went all the way with twin stays (the good is, they are independent all the way, the bad is, extra weight up high. This is the love hate thing.
A sail loft can re-cut the main down (mine has a 14' foot) I have not found any loss in performance, but there should be some, I just was not able to measure it.
as for tuning I have a tension gauge http://www.foreandaftmarine.com/LO-90.htm (shop around this seams high?) and after aligning the stick I tighten them to match. (works great, and if you want to look at it with one wire lost, just lossen the other all the way (you could sail with just one (Hunter has a boat that has the back offset like this) but on one tack there is extra load on the top stay opposite side)
Buds split setup will save some weigh up high! but you are back to just one wire to the top.
I do like My setup = no issues sailing (Just be sure your topping lift line has a self tightening device (Bungy line). But please note; I still don't like the extra weight up high, but it comes with the independent stays.
Fair winds:
Norm
p.s. I removed the boomkin as it allows the vane to be closer to the rudder+/- and it reduces the overall length, and removes extra weight off the back end of the boat. I also recommend any good weight reduction on the bow; like trim and router the platform, and move the chain down to the mast base when possible.