Can you adjust collision boxes for tileset sprites?

I had spikes in my platformer placed as entities, but it makes sense to lay them out instead as part of the tileset. I'm using Ldtk and using tileset rules to layout spikes going around corners works great.

Trouble is as far as I can tell the collision for tiles is only determined by the full tile size (in my case 24x24px tiles) and the spikes are only around 10 pixels long. So the collision extends too far out.

Should I just go back and place them as entities where I can easily control collision box sizes, or is there a way to do it with a tileset?