I googled "history of national weather service sunshine recorder network"
and got the following
http://www.nrel.gov/rredc/solar_resource.html
 
 http://www.nrel.gov/rredc/solar_data.html

http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/

http://rredc.nrel.gov/solar/old_data/nsrdb/1991-2005/

http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/tmy2/

http://rredc.nrel.gov/solar/old_data/nsrdb/1991-2005/tmy3/

http://rredc.nrel.gov/solar/pubs/NSRDB/cover.html
http://rredc.nrel.gov/solar/pubs/NSRDB/history.html
http://rredc.nrel.gov/solar/pubs/NS
http://rredc.nrel.gov/solar/pubs/NSRDB/gifs/4-1F.2.gifRDB/history.html
http://rredc.nrel.gov/solar/pubs/NSRDB/estimate.html
http://rredc.nrel.gov/solar/pubs/NSRDB/appendix_B.6.html

See

http://mrcc.sws.uiuc.edu/FORTS/histories/IN_Indianapolis_Conner.pdf

http://mrcc.sws.uiuc.edu/FORTS/histories/CA_San_Diego_Conner.pdf

National Archives -- Records of the Weather Bureau
http://www.archives.gov/research/guide-fed-records/groups/027.html

http://gcmd.nasa.gov/KeywordSearch/Metadata.do?Portal=GCMD&KeywordPath=[Sensor_Name%3A+Short_Name%3D%27SUNSHINE+RECORDERS%27]&OrigMetadataNode=GCMD&EntryId=gov.noaa.ncdc.C00072&MetadataView=Full&MetadataType=0&lbnode=mdlb1

U.S. Historical Sunshine Data (DSI-9788)

3. Historical Sunshine and Cloud Data in the United States, CDIAC NDP-021/R1 [CDIAC_NDP21] (http://gcmd.nasa.gov/KeywordSearch/Metadata.do?Portal=GCMD&KeywordPath=%5BSensor_Name%3A+Short_Name%3D%27SUNSHINE+RECORDERS%27%5D&OrigMetadataNode=GCMD&EntryId=CDIAC_NDP21&MetadataView=Full&MetadataType=0&lbnode=mdlb3)
 This package contains monthly sunshine data from 240 U.S. stations (including Puerto Rico and nine Pacific Islands) and monthly cloud amount data from 197 U.S. stations. The longest periods of record ...

6. Airways Solar Radiation (DSI-3281) [gov.noaa.ncdc.C00044] (http://gcmd.nasa.gov/KeywordSearch/Metadata.do?Portal=GCMD&KeywordPath=%5BSensor_Name%3A+Short_Name%3D%27SUNSHINE+RECORDERS%27%5D&OrigMetadataNode=GCMD&EntryId=gov.noaa.ncdc.C00044&MetadataView=Full&MetadataType=0&lbnode=mdlb3)
 Airways Solar Radiation is historical digital data set DSI-3281, archived at the National Climatic Data Center (NCDC). This is meteorological and solar radiation data. The meteorological data is a ...

10. SOLMET Hourly Solar Radiation and Meteorological Surface Observations (DSI-9724) [gov.noaa.ncdc.C00047] (http://gcmd.nasa.gov/KeywordSearch/Metadata.do?Portal=GCMD&KeywordPath=%5BSensor_Name%3A+Short_Name%3D%27SUNSHINE+RECORDERS%27%5D&OrigMetadataNode=GCMD&EntryId=gov.noaa.ncdc.C00047&MetadataView=Full&MetadataType=0&lbnode=mdlb3)
 SOLMET Hourly Solar Radiation and Meteorological Surface Observations is historical data set DSI-9724 archived at the National Climatic Data Center (NCDC). SOLMET was designed to provide the solar ...
 20. U.S. Historical Sunshine Data (DSI-9788) [gov.noaa.ncdc.C00072] (http://gcmd.nasa.gov/KeywordSearch/Metadata.do?Portal=GCMD&KeywordPath=%5BSensor_Name%3A+Short_Name%3D%27SUNSHINE+RECORDERS%27%5D&OrigMetadataNode=GCMD&EntryId=gov.noaa.ncdc.C00072&MetadataView=Full&MetadataType=0&lbnode=mdlb3)
 U.S. Historical Sunshine Data (DSI-9788) is a historical digital data set in archive at the National Climatic Data Center (NCDC). The major parameters making up this data set are as follows: File ...