A system includes a processor configured to receive a text message from a remote device including an instruction for a vehicle system. When a magnetic core which is reduced in thickness for adaptation to a high recording density is inserted in an opening of a size conventionally formed in a magnetic head of a standard recording density type, a spacer made of a material equivalent or identical to that of a slider is inserted between the magnetic core and the inner wall of the opening. Embodiments of the present invention can also be used to bill subscribers for the use of content on a per-application, per-user basis for wired subscriber devices as well, using the same techniques. In this manner, the display can be readily removed from the mold. The etching process comprises: a first etching step for pre-defining at least one alignment mark and a second etching step for defining desired semiconductor device patterns on said wafer surface and completing said at least one alignment mark.