My Heoroh is on a Gemoro in Kesuvos but is possibly more Noygea to Horoyios where the Gemoro brings this Mishnah from.
Shteyt in Gemoro Kesuvos Daf 45a at the bottom the Mishna from Horoyos about a Sheggogo a Kohen Moshuach or Nosi(Melech) make and the various Korbonos they have to bring Vechulu.
My Heoroh is on 2 Rashis, Firstly D.H. Chotu why does Rashi mention the Nosi first before the Koyheyn if the order in the Pessukim is Koyheyn and then Nosi and why on the Omud Beys in Rashi d.h. Deozil why Rashi only mentions Soir the Nosi's Korbon and not Par the Koheyn Hamoshuach's Korbon
1) The order of the Mishnah in Horiyos is to first explain "Eizehu Nasi" (at the end of this Mishnah) and only then "Eizehu Mashiach." Rashi is following the order of the Mishnah quoted.
2) As Nasi is the first one mentioned in the Mishnah and there is no practical difference (besides being long winded if he would mention both), Rashi uses the example of the Nasi.
All the best,