Drop-in safety parts are iffy. If it works fine, if not, oh well. Can't suggest anyone's in that category as all the good ones need, thankfully, fitting. To many tolerance stacks to make a reliable part like that with out fitting. Grips often even need fitting.:biglaugh:I want to change from Ambi Thumb Safety to a right side thumb safety, looking for suggestions of which one might be a drop in style?