Looking to get some advice, I have a late model Jackson DKMG (with emg 81/85) which I want to replace with Dimarzio Crunchlab/Liquifire pickups. I've read it's a little more complicated going from actives to passives than vice versa, and this is my first pickup change on a guitar.

I know that I have to replace the 25k pots with 500k. I've read that I've had two options, one being switching them with poorly made pots that will fit the smaller hole, or buying high quality pots and drilling a larger hole so they fit. I prefer to go with option two, even if I have to pay someone to do it. First question, which high quality pots do I need?

Second question, aside from the pickups/pots/mono output what else would I need?

Thanks in advance. I searched and didn't find all the information I was looking for, hopefully this thread can serve other in the future.
I dont know where you heard that, but its the exact opposite... It is much easier going from active to passive.

If you get pots made by the same company, they will be the same size, and you wont need to drill. Who said that bad pots have a smaller shaft than good ones?

You also dont need to switch out the jack. Just dont use the 3rd lug on it.
Unless you had some weird non-standard pots to start with, the 500K ones should be the same size. Guitar pots are almost universally a 1/4" shaft on a 3/8" bushing. You can still get good smaller pots if you really need to, though, so that's not right either. CTS and Alpha are standard, quality brands.

As mentioned above you don't have to change the jack.

You'll need a new tone cap as well. .022 or .015 are good, but you can mess around with values if you like.

You'll also need to get a ground wire. That's the part that might be more complicated going from active to passive. Traditionally the grounding wire goes from the bridge or trem claw (it's soldered on) and then connected to the volume pot, where it's used as a star ground for the rest of the circuit. Just drill a small hole between the trem cavity and the control cavity, which is easy on your guitar since they're right next to each other.
Just did some more research about the jack, thanks! Still a little confused about the pots though...
Most guitars built overseas come standard with that "metric" smaller pot shaft diameter. My MIC Epi was the same way as I'm sure my MIK Ibby is. When I replaced the electronics in the Epi the new pots were the larger "standard" size shaft diameter...I just took a dowel with some sandpaper wrapped around it and went at it for a bit until the new pots fit. Using a drill or dremel just opens up the door for a horrible wood chipping accident so I chose to do it the old fashioned way.

Like the others noted, caps and ground wire and maybe new knobs if changing the shaft diameter and that should do it.

Tip: Cut a small piece of cardboard from a box to lay over your electronics cavity and poke holes for your switch and pots in relative position. Solder everything together there where it's easier to maneuver the iron and wires then drop into place and tighten everything down. If you want to really clean it up use some heat-shrink tubing or wire looming to keep wires together, or get some tiny zip ties.
Ibanez RGT6 EXFX
Fender American Stratocaster
Epiphone Slash Goldtop Les Paul
Carvin DC-135
Washburn G-5V
Taylor 214CEG

EVH 5150 III
Peavey 6505+
Line 6 Flextone III
50s Valco Supro
Got this done over the weekend. Such a major improvement over the EMG's, Thanks for all the help!