Electrical Disconnects for condensing unit
The following is from the 1999 NEC (my 1990 NEC hard copy has the same wording in the same location) so it has been there a long long time:


  440-14. Location. Disconnecting means shall be located within sight from and readily accessible from the air-conditioning or refrigerating equipment. The disconnecting means shall be permitted to be installed on or within the air-conditioning or refrigerating equipment.


Good luck with your project!