This depends a great deal on what sorts of troops you are looking at, but, basically, they are what Americans call "Cuera Dragoons", about which there are two of our MUIA plates. Published some years ago (see our index) but copies can be gotten from our administrator, Mr Sullivan.
The first detailed regulation I know of dates from 1780 and is appended below, my translation:
Uniforms, weapons and accoutrements for officers, decided by the Commandant-General.
(Order issued at Arispe, 21 September 1780 by Antonio Bonilla, Secretary to the Commandant-General of the Provincias Internas of New Spain)
All officers will have a dress uniform, consisting of a coat of blue cloth from the King's factories, with scarlet collar, cuffs and lapels, laced with two narrow gold laces of three threads each, breeches of the same cloth, buff waistcoat, with gold lace slighlty wider than two fingers wide, gold buttons, and a tricorn hat laced with the same lace.
This uniform must be worn only in the Presidios or during the special holidays of the year, the birth and birthdays of His Majesty, the Serene Prince of the Asturias, and of the Royal Family; and outside the Presidios in the settlements when they have to travel on command or for a purpose which obliges them to take up residence for a few days, making sure this regulation is especially observed in the places where resides the Governor of the Province, the Inspector of any other high ranking official in the cities, or towns or large villages where are found subjects of distinction and character.
The undress uniform of the officer will consist of a short coat of blue tripe or cloth with the same facings as on the dress uniform, having on both [types of coat] the epaulettes to distinguish the rank, a short waistcoat of linen, chamois or buff cloth with a narrow lace, breeches or cloth, chamois or tripe, black or white brimmed hat worn a la tendida [turned up on one side] laced with gold, and cape of blue cloth.
This undress uniform will always be worn in the field, in the Presidios, and in the settlements in which they are passing through and do not intend to spend a few days, presenting themselves wearing this uniform to any high ranking official. In the summer, it is permitted that this undress uniform be made of light material, but in the colours described and there will be no objection to the use of the redecilla [hair net] and chamois boots which will be in the style of the country and called campaign [boots], and sarapes o mangas [blankets or cloaks] of blue or scarlet cloth laced at the oppenings; the first [hair net] to protect the hair which should be cared for often in the camps; the second [boots] are the most useful for the vaquero [cow-boy] style saddle, since they are easily put on and off, are not unconfortable for the legs, and protect them from the insects which tend to enter by the eylets of the dragoon type boots; and the third [blanket - a "poncho" obviously] covers the person and his weapons against the hot sun and the rains.
The arms of the officers will be the same as that of the troops and of the same calibre and size, except that they will be of better quality and manufacture.
The 2nd Lieutenant of the Light Troops [tropa ligera] will not be permitted to use the leather jacket and he will carry the same weapons as the soldiers of this type, the same being understood for the Sergeants and Corporals.
As to the saddlery, the officers who are confortable with the bridle saddles which they call mestiza can use them, or if they prefer the vaquera, but it must be made as that of the soldiers, the armor being also permitted, of better make and quality.
(Bancroft Library, California Archives 15, Tomo IV, pp. 134-136. Translated from Spanish)
The lapels appear to have been abolished foolowing the instructions below:
Arguello to Bonica, Monterrey, 17 December 1794.
The order on the trooper's uniform according to the royal regulations for Presidial troops is understood - will requests that the jackets for the Sergeants, Corporals and soldiers be "with scarlet cuffs and collars only, explaining in the Memorandum to omit the lapels."
(Bancroft Library, California Archives 7, Tomo XII, p. 143. Translated from Spanish)
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