Just searched on the forum for the Rit dye key mod. Got the UK source so will order some up.
Looks like people have had mixed results dependant on the plastic/temp/salt/concentration/time.
Willing to give it a go, but in the event of it all going wrong, is there anyone who knows where I can get replacement keys in the UK?
If I've just got to get a second Model M, it could get expensive real quick.