Removing Hacksheild should happen automatically.
If you have experienced a hacksheild crash or error, then the logs & files remain behind.
Hastur stated that it was having difficulty in being removed from some clients, I am not 100% sure but I think it was due to Hacksheild storing information about users.
One method is to try using "dummy's" patcher from the official forums.
This will delete unnecessary files from the //Gravity directory.
Once deleted & fully patched - run "Full Check" using the normal patcher (dont use dummy's permanently)
Full check SHOULD remove hacksheild information from the exe.
Otherwise you could try delete the folders and files from:
//Gravity/Requiem/ "HSmsg(?)"
and
//Gravity/Requiem/System/ "Hacksheild"
Then running full check.
NB: even if "full check" gives you error "client is corrupt - reinstall" it should still sort out the hacksheild folders & files before it checks the .vdk files which is where it usually stuffs up.
I am not 100% sure if this will work for you because for me, Hacksheild was successfuly removed without any problems automatically. One day i logged in, and it was gone ^_^
Good luck