How to Mosaic DRG (.sid) together?

[SeanWineland]

I have downloaded DRG's (.sid) files for the entire state of West Virginia, in hopes of mosaicking them together for use in my study of historical land use patterns within watersheds. 

My question specifically is how to mosaic them together seamlessly without the black and white backgrounds surrounding them currently. 

Below is an image of just all the raw files loaded and displayed in ArcMap. There are white areas where two images overlap and black areas as well (I turned off most of the black background in the symbology settings)

A more fine-scale example below shows the same area with one specific layer turned on (left) and the same later turned on (right)

Is there any way to mosaic these images together for a seamless product that could be used to clip to individual watershed boundaries and for digitizing features within those boundaries from this mosaic? 

Any help would be greatly appreciated!

[DanPatterson_Retired]

Although sid is a supported raster format and esri uses parts of FME's engine, they are pretty well readonly

Supported raster formats .... so although nice and compact, they are pretty useless if you need to get them out to a common format... perhaps Mosaic Datasets can use them, as suggested by Curtis Price‌ in your parallel thread... If not, then they will need to be in another format, assuming the sid files are collar-less to begin with

parallel thread

https://community.esri.com/thread/204355-easy-way-to-remove-collars-from-geotiff-of-usgs-topo