It is my understanding that if the mentioned file is removed, the system will re-add it back, so removing it would not be the best way to go.
The ciphers cannot be added or removed manually, as it would require root permissions, which are not available in MXP endpoints.
There is a bug for MXP endpoints for old versions, and it basically resolves a vulnerability for RCA ciphers, that includes all RC4 64 bit ciphers.
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCux88407/?reffering_site=dumpcr
I hope this helps.