Because PO never waxed my 81 300D, tops of exterior door handlse lack significant amount of chrome. Today I purchased repl;ace door handles at local salvage yard (use parts supplier). Can a DIY'er readily exchange the lock tumblers in the replacement handles with tumblers from the ones being replaced, or does this require special knowledge, skill and tools of locksmith. I first thought I may be able to disassemble them; then reassemble them using the appropriate "keeper" parts, but I noticed couple of small rivets in each unit which may impede such a task. Any tips? TIA