Peter & Gordon's "Lady Godiva"

This month, I learned the bass/low brass part for Peter & Gordon's "Lady Godiva" (I'm not sure if the low brass instrument is tuba or euphonium).  Certainly for the first few measures, they play the same thing, and I think they play the same thing throughout the rest of the song, but it's sometimes a bit difficult to tell.  Some of the subtleties in my notation might be more brass than bass just because it's easier to pick out in the mix, although - as always - there's the disclaimer that I might have something wrong.