Melody notation without rhythm?

The current method I am using for transcribing my trumpet parts for my Salsa band involves writing the letters of the notes on plain paper (A, A, Bb, G, A, Bb, C etc.). This works pretty well as a lazy shorthand - it only contains the notes and not the rhythms, so it does rely on me being able to remember the rhythms. But it serves.

What I'd really like to do however is convert my childish notation method into digital notation on Musescore. This would allow me to transpose the key easily and create harmony parts easily (which I need to do now as we've gained a flute player).

The barrier to doing this is my inability to ascertain the correct durations for the notes I play. I could probably transcribe Mary Had a Little Lamb, but these fast and intricate Latin trumpet solos are beyond my skill level to notate properly. I I can find the notes on the stave well enough, but figuring out how to write the rhythm correctly is something I'm finding really tough.

I know I could spend the time learning how to do this properly, and improving my musical knowledge in the process. But the reality is that for now I just need the notes in digital format, even if they're all crotchets, because then I will be able to transpose pieces and create harmonies. It's the digital notes I need, not the rhythms.

Is there a way I can remove bar lines and just create bunch of crotchets in a line? I've tried doing this and it just adds lots of rests in random places, which becomes confusing.