As there are few specific introdution pertaining to the spelling rule of Munster Irish, I’ve collected some sources to compile the article related to the rules. It may contain errors. If you find one, please leave a comment to let me know. GRMA.
Besides, Irish spelling rules are somewhat complex, they will not be listed wholly. Reading The Irish of West Muskerry, Co. Cork (by Brian Ó Cuív) may help if you’re insterested in.