Let's look at the physics.
My Calmini Winch Bumper hasn't cratered with my Warn 6000 winch, so I have empirical evidence that it's OK.
BUT - just because you can put a 9000 pound winch on that Calmini bumper, doesn't mean it will stay attached to your Track/Kick under max load.
So - if you're in questionable territory, you use a snatch block - that is, a pulley at the far end, and loop the cable back, say for instance to the welded loop on the frame.
How is that better? Like this: If I use a snatch block, the weight is divided between the span from the winch to the snatch block, and the span from the snatch block, back to the frame - so if I'm pulling 10,000 pounds (eek! - yes, with my 6,000 pound winch), that's 5,000 pounds to the winch, and 5,000 pounds to the frame (really - that's how a snatch block "extends" your capability).
If you're ever in doubt - double up your line, and use the snatch block. Note, that it will only be half as fast - be patient!
But - you say My Warn 6000 only came with 80 feet of steel cable! that's less than 40 feet, using a snatch block!
No problem. Throw that nasssssty steel rope away, and get some
1/4 inch blue synthetic winch line (rated at 9,200 pounds) instead - I have
175 feet of the blue stuff on my Warn 6000.
Get it from Scott, at Rockstomper.com:
http://www.rockstomper.com/catalog/recovery/ropes.htm