I have to repair a Grade Select board from a fuel dispenser unit, and it has a proprietary chip in it which I can't get replacements of for obvious reasons. I can however find similar chips which have the same number of pins, form factor, and are also LCD drivers. What are the chances that these drivers will be interchangeable with the ones I'm looking to replace? Basically I'm asking if all or most LCD drivers will use the same or very close pinouts and internal circuitry, or if they don't. What is the potential danger in trying a chip which may not work?