Which fuse does what? : MGB & GT Forum - mgexp Sep 26, 2012the top two fuses are for lights on either side of the car. the third fuse is hot with the ignition on. and the bottom fuse is hot all the time. when i was cleaning my wires/fuse box connections i reconnected my fuel pump wire to the wrong terminal and it wouldn't work. i switched it to the correct one - the third one - and it worked again.Fuse box conversionJun 06, 2017fuse box location? : MGB & GT ForumOct 22, 2015Best MGB wiring diagrams I've ever seen : MGB & GT ForumMar 01, 2007See more results mgb fuse box | eBay Find great deals on eBay for mgb fuse box. Shop with confidence. Skip to main content. eBay Logo: Triumph TR6 MG MGB Mini Cooper Fuse Box Fusebox Lucas 37536 37552 See more like this. vintage vw bus porsche 356 bmw 2002ti 1600tii e10 mga mgb alfa mg mbz fuse box. Brand New. $34.