How to convert 23andMe "I" numbers to "RS" numbers?

Is anyone aware of a good source or forum discussion that describes how to convert the 23andMe "I" numbers that they use to conceal in some cases pathogenic disease causing mutations?
There used to be a member on this site that created a database that would convert many of the "I" numbers to "RS" numbers but she is no longer active.
For those of you who are not aware of what I'm asking 23andMe uses their own internal numbers that start with the letter "I" to marker various things for their own data testing.
In some cases the number simply represents a position that does not have a corresponding SNP. However they also conceal particularly high risk snp's to presumably avoid FDA scrutiny.