Here's a nice view of the BREAK/NO BREAK wiring and toggle activation switch. With this MOD, one can disable an accidental softboot caused by pressing the BREAK key on the keyboard. Click image for larger view.

Here's the view from the underside mid-board edge conenctor. From this angle one can see the TAPE toggle (bottom right) and to the left of the large circular fan opening, the serial port. (Follow the purple/blue/green wires) Click image for larger view.

Pictured is a view of the mod wiring from the underside of the the corner edge connector. From here you can see the SUP-R-MOD RF adapter, video port and cassette ports. Click image for larger view.