OK, not sure why you don't have a one-year, multiple entry Non-Immigrant B visa but maybe there's a reason?

Personally I would go through the red channel and declare these items, with a list and estimated value. The chance of getting caught in the green channel might be slim but if caught you will be in for an experience which will require a lot of time and money (more if paid before the end of the curent police shift; less if not but some time in custody) to extricate yourself. Further you may be deported and denied entry in the future. Enforcement of Thai laws can be somewhat capricious.

Moving to Thailand with a legitimate visa does allow one to bring in many thousands of dollars worth of personal belongings duty-free, so not sure what you did wrong 8 years ago?