Ken, I've been reading all your builds and they are fantastic! I really love the look you have - stance is perfect.

I bend square tube by cutting slits like that for the signs that I fabricate all the time. One thing to speed it up a bit and use less filler is to put the cuts on the inside. Another thing that makes it quick to determine the distance between the cuts is to lay out the curve on the table and lay a tape measure on it - whatever increment lays on the 'flat' of the curve is the spacing for the cuts.
keep up the great work!
Mike