First, don't bypass the ignition resistive wire if you're still running the duraspark ignition module, which it sounds like you are. You'll kill it. Sounds like the ignition coil probably got upgraded to a hopefully tougher unit with the juicebox you did, but that still stresses your ignition module if the coil gets to chew on 12v unregulated. You'd have to upgrade the ignition module or go with a different setup to do that.
Second, if it pops as soon as the key is cycled to on, you have two choices. One, start disconnecting crap tied in to the IGN LPS circuit until the fuse stops blowing. Or remove the fuse and take a DVM to the downstream side of the IGN LPS port on the fuse panel, you should see 0 resistance (or very low resistance) to ground. Start disconnecting things one at a time until the resistance spikes. Both options are a process of elimination, but you're essentially shooting in the dark here. I would disconnect the gauge RED leads (I terminal feed, illustrated below) , the 4wd indicator bulb, and also the EECU 60 pin connector, and then try it to see if it pops again. That's a quick way to see if the short is likely to be inside the passenger compartment.
See what happens after disconnecting those items.
If you're concerned about the ignition module and the passenger compartment items don't resolve the short, disconnect the ignition module wiring plugs. Keep doing things like that and retrying the fuse one component at a time until the fuse doesn't pop. Give a few of those ideas a try and see what happens...