Do upgrades of the same type stack?

I've noticed on my multi-tool that if I can only have up to one of a specific upgrade but can have multiples of the same type of upgrade if they give different bonus amounts.

For example, let's say I've got a mining laser and the level 2 upgrade that gives it more combat damage. I go into the crafting screen and see that I can still craft and add the level 1 upgrade that gives it more combat damage, but I can't create a second level 2 upgrade for it.

If it has both the level 1 and level 2 upgrade, do they stack, or does it just take the best one? I'm currently coming at this from the reverse way where I've got a multi-tool that has multiple upgrades of the same type on it that I want to dismantle to make space if the lower-level ones aren't actually doing anything, but am afraid to try it out because I don't have the blueprints to recraft them if it stacks. Plus, I'm not entirely sure the best way to test it.

Solution 1:

The answer is yes they do stack, but only if they are in the correct position. They have to be adjacent to one another horizontally. I'm not exactly sure yet if order matters (ie level 1 on the left, level 2 on the right). But, if you do have it in the correct order, a yellow box will appear around both of them. No yellow box, then not stacking. I have personally tested this out on a scanner, and it gave me a massive increase to its range.

Solution 2:

Upgrades of the same type will stack regardless of position. For instance, if you have a +1 and a +2 upgrade to your heat resistance and they are not adjacent in your inventory, you will be protected from heat damage for a total time that is equal to the time granted by the +1 and +2 upgrades. If they are adjacent, you will be protected for slightly longer.

In short, yes they stack, but if they are adjacent, they will stack AND you will get a bonus on top of it. For more info about how the adjacency bonus works, see this question.