Looks like according to this that it could be good for 380 hp.  if needed. 

http://www.cptdb.ca/wiki/index.php?title=Caterpillar_C10 

Look at the bright side you will never make enemies by passing everyone two miles from the elevator to get ahead in line with it.  Find a refer trailer and just "Draft" it. 
If you get it, just think of all the extra time you will have on your hands not having to check truckpaper and craigslist everyday for one!  Been there done that!

I look at it this way, it most likely pulled a 80,000 lb load 80 to 90% of the time, someone drove it 500,000 miles already so it must be able to make it from point A to point B with that much hp.  Put a set of dual 8" stacks on it and no one will know the difference.