There is one fuse holder in my glass fuse block that was melted in my van. Could someone putting in the wrong fuse create a bad connection causing this? I came across a replacement block, but would it be worth wiring in a new one?

 

absolutely...

evidently the connection wasnt tight enough -- more than likely...OR that circuit had a really high draw very near the blow point of the fuse...for a very long time...

 

In that case, would wiring in a new one be the best option?

 

a new circuit yea---i dont think you need to do the whole box unless you want to...You have to remember we are dealing with used parts...if you have a part with possible multiple points of failure...and only one is failed - they just fix the one...
Used parts can be an issue..especially electric ones

 

The two janky fuse holders aren’t entirely important to the functionality of the car, but it would be nice to get them fixed.

 

Wow, that's burnt.... WTF happened??? That had to get REALLY hot. What circuit WAS in there??

 

yea - which one did that?

 

From what I know, it was previously a 20amp powering the dome lamp, courtesy lamp, stop lamp, reading lamp, glove box lamp, ignition switch lamp, time delay relay and lamps, and power door lock relay. Or at least that is what was listed connected to that fuse.

 

Wonder which one smoked it.......

 

it is one of those