(I already had the CUDA 11.7 SDK installed, likely unnecessary)
Then from a Visual Studio 2022 Developer Prompt (x64):
pip install torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/cu117
git clone https://github.com/facebookresearch/detectron2
cd detectron2
set DISTUTILS_USE_SDK=1
python -m pip install -e .