Description:

I'd like to be able to replace an upgrade with a higher tier upgrade from within the GUI.

You can already do that, by just clicking on the upgrade with another upgrade or by rightclicking the drawer with a higher upgrade in world. You can only do those things if the new storage capacity can hold the current items.

I just tested in with no other mods installed, and it does not work (at least consistently).

My first test I tried with an oak drawer with an iron downgrade and a copper upgrade and ~128 items in it. With that setup, I could freely switch the copper upgrade for a gold upgrade. (I used an iron downgrade to more easily fill the drawer enough to require a card.

At this point, I thought it might be a mod interaction, so I tried testing with various more or less plausible mods from the modpack I am currently playing (Monifactory) and had the same result (i.e. being able to switch upgrades). Eventually, I tried that same first test in the pack itself and discovered it worked.

At that point I realized that it sometimes works and sometimes doesn't (as this isn't the first modpack I've played where I have been frustrated by being unable to switch upgrades).

After doing a bit of testing in the modpack, I returned to my instance with no other mods installed, and tested an oak drawer with a single copper upgrade and ~2.7k items. I was unable to switch the copper upgrade for a gold upgrade.

I suspect this may be related (tested on 1.20.1 with no other mods): If I have a drawer with 65 items and a copper upgrade, I cannot install an iron downgrade into it (either via the gui or by clicking in-world with the upgrade.

Something that does work for switching upgrades: if all the upgrades slots are filled, clicking in-world with a higher tier upgrade will swap out a lower tier upgrade, even with more than 2048 items in the drawer.

I also discovered that if you have a drawer with a copper upgrade and an iron downgrade and 512 items, you can remove the upgrade leaving 512/64 items in the drawer.