A very simple resource pack that ever so slightly remodels the default mob spawner with a new set of textures for the sides, interior, bottom and top to make it a little more in line with the new trial spawner. This pack has been made with clarity in mind so you can quickly glance at the center and tell which mob the spawner will spawn.

Extra notes:

This spawner has an emissive texture for the skull's eyes you may delete spawner_e to get rid of it.
you can combine this into your own pack but if you upload that pack give credit to spamrock studios.

requires optifine (forge) or continuity (fabric) for the glowing texture but should work fine on vanilla otherwise.

Stuff seen in the screenshots

Pixel consistency by Thanos
Rethinking voxels by gri753