If SID does preclude image clipping (only ECW & TIF here at the moment), just convert the image via Raster Design, no?
NO, not everyone has Raster Design
I try not to suggest solutions that require additional purchase.
If I worked for autodesk that would be different.
... I didn't realize that was a requirement for making posts here... Like you were never gone; welcome back grumpy.
We have infrastructure design suite 2013, so I do have Raster Design on my computer. However, when I opened it, everything looked the same as civil 3d, and I couldn't find any special raster design options. What I ended up doing was using ifranview to desaturate the mrsid files, save out as jpg, then inserted back in the drawing. The sucky part about that is, when you convert with ifranview, it stips out all coordinate data, so after the images came in at 0,0, I had to scale and move them to match the size and placement of the mapwspace mrsid, clipped them to fit my area, and then turned off the displaly for the mapwspace mrsid images.
I wasn't pleased with it, but it worked, and at the time, I just had to get an aerial overlay, and the above round-about method got me what I needed.
FWIW -
Raster Design is a glorified add-on / plug-in which is loaded into AutoCAD, Map 3D, Civil 3D, etc. and cannot launch in it's own editor. For this reason, we incorporate RD into our production profiles, such that RD is demand-loaded (i.e., CUIx, SFSP, etc.).
Not sure which 'raster design options' you're after... See Raster Tools tab in Ribbon, perhaps IOPTIONS Command specifically?
I typically attach raster images via MAPIINSERT (doesn't demand-load RD), or IINSERT from our library for each county, state, etc. on the network, and export attached raster images using IEXPORT, as TIF (with JPEG compression), and re-associate the exported image via World File, where all exported files are located within the project's directory tree to make it easy for others, etc.
Not sure where you're getting your SID files, but they should come in, and export out with coordinates in my limited experience.
Cheers