Hello! I want to ask few questions about optical pick up replacement on MZ-N10 unit. So i found where to buy new optical pick up assy,question is,how difficult is make all adjustments to fit right? Is there adress (or something like that) where to type new opt. pick up LD current code,or it is not necessary? I bought used MZ-N10 walkman and found their lense are scratched,or maybe dust is under that lense and that makes an optical illusion,when i look at lense with magnifying glass? In service mode error code is 138 NG,which is RF gain adjustment? And sorry for bad english!