Preamble
The removal of the building is not a disposal of an asset and on removal, the building and land are split into separate assets (see TD 93/D75).
The cost base of the post-CGT building and land is apportioned under subsection 160ZH(12) of the Income Tax Assessment Act 1936.
On relocation of the building to the pre-CGT land, the building continues to be a separate post-CGT asset (see TD 93/D77).
Any capital improvements made to the pre-CGT land will be a separate asset provided the requirements in subsection 160P(6) are satisfied.
The pre-CGT land remains a pre-CGT asset. Upon disposal of the land and building, a capital gain or capital loss may only arise in respect of the building (and capital improvements if they are treated as a separate asset).