How to put my custom menu at the top?

Good morning everyone,

Would appreciate a little assistance with a problem I seem to be having.

I’m currently writing a bespoke plugin for a client who will be using WordPress for his site, and I need to add a top level menu into the admin section. This, I have successfully managed to do with the help of the Codex references. However, by default it places this custom menu at the bottom of the admin sidebar on the left which can’t be seen until scrolling down. I wondered, is it possible to somehow set a parameter to make it so my custom menu is near the top, preferably under the Posts/Pages/Comments etc block as it’s own menu?

Any help appreciated, if someone could point me in the right direction I would be grateful.

Regards,
Michael