The 175A “mega fuse” and heavier gauge wiring was GM RPO ZM9 (at least in 1998). The mega fuse and holder mounted on the passenger’s side of the radiator shroud. Heavier wiring was used from the alternator to the fuse and from there onto the fuse box on the driver’s side firewall.
The fuse was between the
alt and battery, not the alt and fuse box.
Why OP removed it isn’t clear. Maybe some prior owner messed it up.
Details are here and in some posts that follow it, including a schematic from the 1998 service manual:
I need a picture of the battery cable routing to/from the fuse located on the fan shroud. 99 Suburban 2500 4x4 7.4. An actual picture would be greatly appreciated. TIA
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