I came very close to owning a 580E. They are a very different machine from the 580K. They are, I believe European made, Italian, I think.
The 580K is a machine with lots of ductile iron parts that can't be welded. I believe the E had fewer ductile parts. I believe they use the ultra common Cummins 3900 CC four cylinder. The one in my 580K Case claims is built by Case, but is identical to the Cummins in my Dresser bulldozer. I've had torque converter problems (slipping when hot) in two 580K tractors. I have two friends who one at a time have owned the same 580E since new. They've done recommended maintenance, but had no problems.
I think some E series have detachable backhoes, study the mounting hardware carefully.`