A Plugin to Restrict Permissions related to a SECOND Admin?

This is my issue:

1) I've built a website for a client.
2) I want to give him access to most plugins (these plugins may require Admin role for the client to use it).
3) But I need to restrict some of the menu items for this client (menu items that obviously appear to all Admins).

Is there a way to either:
* Restrict some menu items or plugins for a specific user (rather than for a specific role/level)?
* Make the user an Editor and enable specific plugins that are written only to show for admins?

Thanks for your help!