If you're in love with classic Fuji (and other Japanese) bikes, and haven't already, you might want to check this book out ... https://www.amazon.com/Japanese-Stee.../dp/0847861708

I met the author and bought an Opus III frame from him, he mentioned the factory or builder where it was built as being special, but the name escapes me now.

The book is packed with great photos and lots of interesting detailed info.