Go back to pre 1960s and eliminate every single government agency established since.
Eliminate the US Forest Service and the National park service. Eliminate all wilderness set asides.
Turn all those back to the counties-the USFS, and the states-the BLM lands and National Parks. All those are managed under a trust by the federal government. Take the trust away.
The national parks are about the only thing I’d let them keep.
There’s far more trimming they could do than that because if those lands are opened up, they will be destroyed in no time.