Hey Chug,
I bought a used 72in Rankin and wrestled with it on the back of my BX. I knew it was too big but the price was right. Did a lot of work with it (grading a road/trail across and down a steep slope on my property). Actually move a lot of dirt with it but was fighting it all along.
Finally got smart and cut it down (using a plasma cutter) lopping off 4.5in on each side making it 63in wide. World of difference! Went from tail wagging the dog to something far more forgiving and easier to control and drag. I would have cut 6in off each side but the removable hard edge has carriage bolts that I didn't want to lose on the ends.
My recommendation is do NOT go for a 6ft blade on a BX. I have 2in wheel spacers on the rears making it about 48in max width. A 60in balde will clear the rears easy.... BTW I highly recommend wheel spacers. Especially if you are working on a slope or uneven ground! My :2cents:
Here is a pic what what I was dealing with. Sorry the blade isn't on but you can see the trail I was carving. BH on to tear out a stump in the path.
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