Nice looking unit!
Uh, shackle tabs are supposed to have holes in them. Maybe get those done before the bumper is fully welded out? Cause drilling that by hand without a press "difficult" at best. Flame-cut would be easiest, but the temps will change the metallurgy of the tabs, making them more brittle.
If they are not part of the bumper (yet), I can have the holes punched vs flame-cut for you. The iron-worker press I have access to will do up the 3/4" thick. Due to variances in shackle manufacturers, shackle sizes are not the diameter of the pin, but the diameter of the loop. So a 7/8" (6.5ton) shackle will need about a 1" hole -/+ 1/32"
http://www.jhenryholland.com/shackles.htmOr whatever shackle you plan on using.
Otherwise, dang-fine looking unit. I like how you matched the outside angle to match the fenders and flares.
I'll save the "Stock fender vs tube fender" argument for another day!
Nice bumper, how are you going to test it?