I'm currently trying to replace that very chip (53C80) for another 68kmla member. I'll tell you this much from experience: I think this will be the last request for replacing those types of chips for now. I don't have the right tools to get the job done properly. I'll need an air rework station for soldering/desoldering and the square iron tips for these chips. The technical name for these kind of chips are PLCC, which stands for Program Logic Control Chip. The iron tips are designed to get underneath the folded legs (contacts) and desolder all sides at the same time, allowing you to lift the part away without damaging the traces or legs of the chip.

So when I get this one done, it will be the last one I attempt (successfully or not) to replace the chips on. Better off getting someone else to do it for you who has the right tools or just replace the logic board and be done with it.

73s de Phreakout. :rambo: