Ghost.....
here's the thing.
you don't need dimensions from anyone else.....
because the jeep will tell you what the dimensions will be, and if its a winch bumper, the winch will tell you what it needs to be......
all you need to concern yourself with, is slapping a pair of plates on the sides of the framerails (leave room for a c-rok plate
)
make this be 1/4" crs, the jeep will tell you which holes to use. When the 1/4 plates extend beyond the front of the grill, imagine a winch box going between these points. Make the winch box 3/16" crs.
You don't have many options here. The framerails "are what they are" and the winchbox must accomodate the winch, and the space it occupies, you must consider "minimal". You will have plenty of width to play with, that's not an issue. Without removing the front crossmember of the jeep, anything extending beyond 10" beyond the front of the grill is a waste of space and approach angle. anything beyond 6-7" below the bottom of the grill is a waste of space and approach angle (if I'm remembering these dimensions right, My jeep doesn't live at home) everything that happens on either side of the 1/4" plates is up to you, and the winchbox is your "maximum", and your corners are you "minimums".....if your bumper "skin" tapers off to the corners too quick, it won't have strength, if its too fat its a waste of space. I used 8ga. for my skin, and made a return flange under the winchbox so that the foreward two mounting holes (for a winch other than an 8274) has an 8ga. plus 3/16" "sandwhich" for ULTIMATE winch box strength.
So you see what I'm gettin' at, that the jeep and the winch, designs the bumper for you? About the only difference between aftermarket bumpers is small differences in shape materials and manufacturing methods, but the design process is basically the same....
start with the "knowns" and work outward and you'll see where you have room for asthetic concepts.
build a 1/2 scale model out of foamcore or cardboard, or even a fullscale model before you go to the real thing. you can work out most of the design challenges on throw-away materials.