I didn't say the brute installation was more 'effective,' just easier to implement & understand. If an existing fuse holder is used, you still have to run your wire up to the back of the fuse block & wire it appropriately. From the looks of MY fuse holder, fishing and then attaching a wire into that location looks like a lot of work compared to what I advocate.
Attaching a single new circuit wire directly to battery terminals is very easy, as is the installation of an in-line fuse holder very close to the wire terminal. If that circuit blows, you know just where to look, it will be on top of everything else.
There is plenty of space under the hood to run wires up from the frame of the truck into the engine compartment, and there are dozens of holes and brackets to secure your new wire with cable ties.
Wally World sells 30 amp inline maxi fuse holders for less than $2. Or you can create your own inline fuse terminals using crimp-on spade receptacles. Crimp, solder the crimp & apply heat shrink tubing to the crimp-on terminal, pick whatever size terminal necessary to bolt on to the battery studs or clamps.
I've taken this a couple of steps further. I have 3 auxiliary power circuits I've wired this way. So the new terminals bolted on to the battery can get a bit crowded.
I converted my battery terminals to marine style battery terminals, these have a huge stud and wingnut on top to allow large cables to be bolted on right next to the battery terminal. I bought an 8" by 1" by 3/16" piece of brass bar stock from McMaster-Carr for less than $5. Made 2 4-inch long pieces out of it. Brass this size is every bit as good for high amperage use as copper, and far cheaper. Drilled & tapped the brass with my usual wood working tools, to allow quick removal & reattachment of what is now a 'busbar' so that the battery can be serviced.
I've attached tape labels to each of the wire sets to identify their function. It's easier to get at these circuits and their fuses than the OEM fuse boxes. I've wired my pickup shell for multiple 12 V outlets, and my cab for a 400W voltage inverter & a 20A circuit for a ham radio.
There is a significant vulnerability in my installation. There is a lot of 'hot' 12 VDC metal exposed near the positive pole of the battery, you really don't want to short this out to ground unless you intend experimenting with 12VDC welding methods.