Congrats!
IIRC, the first 3000s came with roms to get to a Kickstart select screen, sort of in the style of the A1000. The actual rom image was on the HD. This dates from when OS 2.x was still in development. You probably have an original!
Later, when OS 3.x came out, many ppl replaced these loader roms with rom chips containing the complete Kickstart (like most other models and the later 3000s). This is where the confusion begins. There was a special Kickstart 3.1 rom set for your MB rev and tower.
I never pursued this, but, I think some people were able to obtain a KS 3.1 image file. They could leave their machines as originally made AND have the flexibility to boot into whatever version of Kickstart they wanted.