i have the interior kinda gutted right now due to cleaning and what not , had some crazy electrical problems on it earlier this week , fuel level , charge light , turn signals not working , one tail light working , etc .... found the contacts in the fuse block to be corroded both where it plugs in and where the tube fuses clip in , cleaned all the contact points and all is well now , also had to completely disassemble the multi function switch and clean all the contact points there as well and apply some dielectric grease , from what i hear this is all too common on these trucks with age .