D&RGW Snowplows (Question!) *LINK*

This is something that has puzzled me for a long time. Take the K-36 class for example. Some have snowplows on them. I noticed that there are 2 different kinds. For example, the type on 487:
[www.freewebs.com]
And the type on 489:
[homepage.powerup.com.au]
I was wondering on the 487 type, is the entire cowcatcher underneath the plow and they attach the plow to the end of the beam on the cowcatcher's platform (Where little rods that make up the plow are hung from)? On the 489 type do they take off the little step things on the side of the cowcatcher (leave the cowcatcher it self underneath) and using holes in the sides of the plow attach it to the beams using them for support? I was wondering because someone told me that you could just take off the plow and underneath is a cowcatcher. Is this right?
Thanks!
John
Future C&TS Engineer