Custom Records - Remove Attach Functionality on Form?

Hi,

     Is it possible to remove the "Attach" button that is present on a subtab for a Custom Record when it's associated with a Customer? 

     Here's the problem:-
        For example: I need to hold details of multiple services that we supply to a Customer. 
       To do this I define a Custom Record Type "Service" with the Customer defined as the Parent, I add this to an existing Sub-tab "Info".  So on a Customer below my "Info" sub-tab I have my "Services" subtab which lists multiple Service records for that Customer (each on unique to that Customer).
      BUT by default at the top of the list of Service records there is an "Attach" button and a drop-down list of all the Service Custom Records that have been set up in the system irrespective of which Customer they are associated with.  Therefore it's possible for one of our users to select a Service record that belongs to Customer A and attach it to Customer B (& remove it from Customer A). We would NEVER want to be able to do this.