Been here, done this...

Because if you were running TRS2004, the locomotives would show without problems, but their are certain errors that need correction for TS2006 & up. I'm running '10 also.
I downloaded the Southern GP35's today to see what shows...the bogeys did not come...the CG GP35's however, brought their bogeys with the download.
Gisa, wrote a question about upgrading the GP35's for the newer versions of Trainz...Joe has the new mesh, but it will be awhile before he gets this project done.
Here is the thread at RRMods.
The Southern GP35's as you may know, run trade-in ALCo type B trucks. My CMv3 shows only those Geeps as the dependant assets...possibly there are more that use them that I don't have(such as Soo Line, but downloading the Soo GP35's did not bring up '61 or '62).
You'll see on the RRMods thread that I have requested the location of your missing bogeys.
Also, check out what I did by manipulating several RRMods files to produce a correct hi-nose, short hood forward locomotive...
The meshes for these locomotives are in .pm instead of .im format. The texture maps are in .TEXTURE, or binary format, they need to be converted using
PEVSoft IMtoPM &
Texture to TGA tools.
Quickshadows can be used to create shadow files off the .im files also. If your not familiar with these, it only takes a minute to configure them. Save the .pm files to a folder somewhere you can find them.
When you get the bogeys, you'll need to work those same files also.
Run the locomotives through CCP & locate the default .im & shadow.im files.
Also, since there is a thumbnail provided, you can add a thumbnails container(right-click the main folder in the folder tree at top, select...).
I used a cab from a payware GP50...when first offered, the download used a GP50r(reversed) cab...it was short-hood forward & a correct cab was supplied for the ones that wanted it....but that's another topic for later, if you wish...
Hope this helps!
Remember, Joram24 is well aware of this and planning updates, but it will take awhile, so don't ask when it will be finished...and they will be payware, but they will be worth it!