Here is a schematic for your tv:
http://www.givemefile.net/smanuals/t...file/7962.html
go to this site, type in the letters into the box, then click on the link for the models listed. "Download SONY service manual KV-27S42, KV-27S46, KV-27S66, KV-29AL42, KV-29AL42C, KV-29AL66, KV-29AL66C, KV-29SL43, KV-29SL43C repair manual"
Its a 8+MB file. I downloaded and opened it, and its got all you need, nice file and should get you a good start! This schematic has your chassis number on it.