That's a pretty sad looking fuse box. You might be better served in the long run to just replace the entire fuse box. The new box may not come with EVERY fuse you need so if any needed fuses are missing buy new high quality fuses. You'll be happy you did. Also look for any other wiring 'green crusties' and clean them up.. That 'green crusties' stuff is corrosion and it causes resistance in electrical circuits, to be avoided at all costs.
2008 Silverado LT, CCLB, Edge Insight CTS
2009 Arctic Fox 29-5T, Silver Fox Edition, Onan 3600 LPG generator