It was even difficult. For those wanting something more than spray cans, this appears to be a good option. It's based on the '85 RZ350 yellow. They do specify that this is for an entire application and not meant to use as a blend for existing panels. I'll be doing my RD400 in this.
Yamaha Competition Yellow | 0026 | 1985 | OEM AG Series Single Stage
https://tamcopaint.com/products/yamaha-competition-yellow-0026-1985-oem-ag-series-single-stage
Yamaha Competition Yellow | 0026 | 1985 | OEM Amerflint II Series Single Stage
https://tamcopaint.com/products/yamaha-competition-yellow-0026-1985-oem-amerflint-ii-series-single-stage
Yamaha Competition Yellow | 0026 | 1985 | OEM Basecoat
https://tamcopaint.com/products/yamaha-competition-yellow-0026-1985-oem-basecoat
Yamaha Competition Yellow | 0026 | 1985 | OEM DuraFlint Series Single Stage
https://tamcopaint.com/products/yamaha-competition-yellow-0026-1985-oem-duraflint-series-single-stage
Yamaha Competition Yellow | 0026 | 1985 | OEM High Impact Single Stage
https://tamcopaint.com/products/yamaha-competition-yellow-0026-1985-oem-high-impact-single-stage