It would be wrong to change the spacing to fit the letters, the correct solution would be instead using some kind of abbreviations, because there's a reason why those models are called in a certain way. The T1-42, for example, it's called "42" because it has 7 rows of 6 columns so it can only display 42 characters. The T2-24 (the one in your screenshot ) has 5 rows of 6 characters but 6 are not used, so it can only display 24 characters, hence its name.
So we might need to change some wording to make it fit into 6 characters.