Hi James, I endorse all of what has been said here. To give you a wider outlook on what people do or the lengths they go to to clean the cherished vinyl go onto Google and type in 'cleaning vinyl records'. You will get many a no no crazy whacko methods, glue?, to steam (steam vapour), don't discount this latter one because if done guardedly and with the right approach this is one of the best methods I have come across in tandem with the regular methods. A vacuum lift off is a must and this can be achieved by an adaptation of a household vac or better still an RCM. If you want to see what steam vapour can do next time you boil a kettle for a cuppa lift the kettle lid and use a pair of dirty specs (thats if you were 'em) or a plate and you will see just how much water vapour is collected waiting to be towelled off taking dirt with it, go see the demonstrations, ignore the one where this guy completely warps his record and relies on the record to return to shape on cooling down. This is an absolute no can do.
Question; after 27 years storage in a loft with high temperatures in summer and below zero in winter how have your vinyl records faired?