I haven't be on that section at low water in a while, but I think the Class II - III- description is probably pretty accurate. As I recall it's quite continuous, but easy. Not a very long run at all.
Elephant rock is upstream of Buena Vista on the Ark. It's literally labeled "elephant rock" on the 1:24k topo map. Lat/long are: N 38.88465 W 106.15179
Use Acme Mapper for location. ACME Mapper 2.0
Frankly, at these lower flows, you may consider something a bit harder like Browns Canyon. For a beginner, it's a nice time of year to do some swimming (water is warm), and the season is almost over, so you may as well end it on a high note.