Owner's manual has a diagram for it, if you have one handy. The closest I have is a 1992 manual which may not be the same. Depending on how your truck was optioned it's very common for there to be spaces with no fuse.
You may not have all the options that the fuse block can handle....
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93 CHEVY G30 454 4L80E 4X4 SPORTVAN EXT 146 WB
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