How to revalue an asset so that the adjustment is to be amortized to spread over the remaining life?

To use a simple example:

An asset costs $12,000 with an expected life of 5 yrs (60 months), and periodic depreciation is $2000. Halfway through (therefore, at this point there is $6000 of depreciation), the expected life changes to 8 years, and the adjustment is to be amortized so that the periodic depreciation is spread out over the remaining 66 months:

Making the periodic depreciation 90.91.

What steps would I take to achieve this in Oracle?

Thank you for your help!