I'm working on updating the design over at
http://www.dalton.ax/hpdisk/ to be GPIB compliant. Luckily, his original design uses a very similar MCU to a through hole PIC18F series part I had on hand.
Currently, that version connects the microcontroller pins directly to the GPIB bus, which causes problems with having more than one device on the bus. I'm working on adding proper GPIB transceivers to it, and making as many parts through hole as possible, to allow for easy debugging. Currently, the only parts I have not been able to find a through hole alternative for were the USB/UART chip, SD card slot, and SD card logic level converter.
I just finished up my first draft of the schematic, and need to double check footprints and connections before setting up the layout.
If anyone has any feedback or suggestions, particularly for how the DIP switches and transceiver IC's are connected, please let me know!