Thank you Capn and lazy dragon! I appreciate the compliments and recommendations.
I've been researching on whether there was any difference between the color of the pompons of different companies within the same permanent infantry regiment. Although I haven't found a concrete source outright stating the colors, I believe fusiliers had crimson pompons,
cazadores (riflemen) had green pompons, and grenadiers had conical crimson pompons. I believe this based on the following:
Book: The Mexican Soldier, 1837-1847 Organization, Dress & Equipment by Joseph Hefter.Soldier A is identified as a rifleman (
cazador) from the 6th Regular Infantry Regiment. Note the green pompon

Shako A is identified as belonging to a
cazador from the National Guard, Victoria Battalion.
Shako B is identified as possibly belonging to a Grenadier from the same Battalion.
Book: Santa Anna's Mexican Army 1821-1848 by René Chartrand (Osprey)Sketch of an Infantry Grenadier copied from a painting circa 1840.

Despite my findings, there's still a thing or two that make me doubt about my assertion. Shako's A and B from the second image are from the National Guard and not from a regular regiment. Shako C from the same image is identified as possibly belonging to a Grenadier line officer. If my assumptions are correct, why is that pompon crimson and not green? As a counterpoint to this, Hefter's book also mentions that the shortly lived 1840 uniform regulations (they were reverted only a year or so after publishing) specified that pompons were to be crimson throughout all fusilier, cazador, grenadier, and pioneer companies. If pompons were all the same before this, why even specify it?
Might seem like I'm splitting hairs, but detail is everything when painting miniature uniforms

Besides, my battalions are of 32 figures. Four figures represent a company. So I want four figures to represent the cazadores and other four figures representing the grenadiers. This way I can feel I have the whole battalion without having to actually paint eight whole companies of figures

If anybody has any info on this subject please share it!