$ tar tvf ~/.openttd/content_download/newgrf/OpenGFX_Trains-0.3.0.tar 
drwxr-xr-x www-data/www-data 0 2012-01-21 23:16 OpenGFX_Trains-0.3.0/
-rw-r--r-- www-data/www-data 17987 2012-01-21 23:16 OpenGFX_Trains-0.3.0/license.txt
-rw-r--r-- www-data/www-data 280435 2012-01-21 23:16 OpenGFX_Trains-0.3.0/ogfx-trains.grf
-rw-r--r-- www-data/www-data   7054 2012-01-21 23:16 OpenGFX_Trains-0.3.0/changelog.txt
-rw-r--r-- www-data/www-data  10707 2012-01-21 23:16 OpenGFX_Trains-0.3.0/readme.txt

$ grep ogfx-trai ~/.openttd/openttd.cfg
4F472B31|4E0B2D42462F295F36AFBA90D239A323|opengfx_trains-0.3.0/ogfx-trains.grf = 0 14 0 0