67 mustang fuse block

Not sure what you mean(or why you would want to replace Bus fuses with blade fuses...there is no advantage...and it can be argued that you can do a safer emergency bypass of a bus fuse with tinfoil than you ever could with a blade type). regardless of the fuse block you get a fuse is just an interruption in a circuit...one wire in, one wire out for each circuit.

The emergency lights are fused off the cigarette lighter fuse? How bizarre. Anyway, the only thing I see is that there are a couple fuses that use the same input power source...in particular cigarette lighter and courtesy fuses are both drawing from the same input power, as are the radio and heater switch(ignition switch power source there). So assuming you don't want to change things too much, just retain those 2 multi-fuse power sources for the new block....as for running multiple circuits off a single fuse(like emergency lights and cigarette lighter as an example) that is an absolute garbage setup...do you want your flashers not to work if you blow a cigarette lighter fuse plugging in an air pump? Here is what I would do if it were me:

1. Run a different fuse for each and every circuit...there is absolutely no reason for multiple circuits to run off the same fuse.
2. Because you are running a separate fuse for each circuit, you will need to add input power....to do this, run a small power distribution block like this:


These distribution blocks meant for car audio are useful...you input a given feed of whatever gauge and split the output into however many wires you need to power each fused circuit.....so one block would have an input from the ignition switch(just like the wiring diagram shows) and an output for the following fuses: Heater and Radio, the other distribution block would have an input from the battery and output for each of the following fuses: Courtesy lights, Emergency Lights, Cigarette lighter. That will retain stock-like functionality. Instrument cluster is just fused in-line with the cluster wiring. You will need a 6-fuse(min) block to wire it like this.

To be truthful...the wiring setup in vintage mustangs is absolute garbage. For instance...the headlights and taillights are so dim from the factory because they do not have relays in-line. Not really the fault of Ford of course, since relays weren't in common use until a decade later...but there are plenty of wiring upgrades to be done...the fuse block is only the beginning and I wouldn't waste my time if I were you...if you are really serious about upgrading the factory wiring:

You can get any number of 14 or 21 circuit full harnesses off of Ebay for $120 or less. They have a circuit for everything you could possibly want.....you would still need to add headlight and taillight relays, but once you did you would have a full modern system