Are both depreciated over the same useful life?
If not, they are likely separate lines on tax return, each with a separate NBV.
Either way, I would make account numbers more consistent, like
1600
- 1630
- 1631
- 1640
- 1641
If I were your bookkeeper/accountant, I would never guess that 1641 rolls up into 1630.
I'm not a fan of QB roll-up accounts, but if I was going to use them, I would make them unique.
I see so many messed-up QB books, often with entries posted into roll-up accounts in error.