Sorry for interrupting you, but I thought that you might want to know that "1te Ostpreussisches Grenadiers" is as grammatically incorrect as possible.
In German word endings indicate the gender of the word they refer to. 1te "erste" refers to a female word and therefore can't go together with (unless you have an article like das infront) Ostpreussisches which refers to a neutral word.
I don't know if it's intended, but Grenadiers is an English word and in German we say Grenadiere.
Now, correct and historical would be : 1tes Ostpreussisches Grenadierregiment.
No offense intended.