Sounds like you're after a power distribution panel. That's what
I used in my Crown Vic. I bought a police-style hump mount radio
rack for it, and it came with a handy power distribution panel, with
six fused taps fed from a big honking lug in the center. While the
mounting rack was made by Scientific Dimensions International,
the power distribution fuse blocks are actually made by DuraComm.
They take ordinary ATC style automotive blade fuses. I bought this
gear from Tessco (
www.tessco.com), who is aimed squarely at the
industrial/emergency communications market, but they were
willing to sell me stuff too.