This Uniform is the one believed isued to the First Minnesota at Fort Snelling Minnesota. It is also now said, the shirt may have been tucked into the trousers but,  I do not have any sources on this.

In the afternoon on Sat. April 29th, 1861, Mr. George Farrington of the
firm of Calver & Farrington , carried to the Fort and distributed, eight hundred blankets, eight hundred shirts and eight hundred pairs of socks.
They were taken by the soldiers at once. The blankets were red, white and blue, and some green. The Hats and pants were engaged, and were to be ready soon.
On May 8th the pantaloon and hats for the regiment arived at the Fort.
May 9th is also mentioned as a date they may have been handed out.
It was said they were handed out to the companies as rapidly as possible.
It was said that Co. A The Pioneer Guards were served first.

A large lot of arms arrived also but, not quite enough to equip all the companies.
A letter from J.A.W., writes, the uniforms had not arrived. The red shirts of the "Red Wing" contrasted well with the blue and grey of the other companies. When one reads the letter, one might take it as if the Red Wing ,Co. F may have had a red shirt of some kind when they came into the fort. The letter is in my history section. Life at Fort Snelling.
1842 .69 Cal. US Springfield Musket
Private Anthony