Generating multiple (small) pak files to release game under GitHub releases

I have written a simulation of a disaster environment using Unreal Engine 4.16 and Microsoft AirSim and now I am trying to open source the environment binaries. AirSim use GitHub releases for their binaries, which seems like a good solution. However, each binary needs to be less than 2Gb in size and my pak file is 2.7Gb when I run the package manager. I know that there are ways of splitting the pak file using ‘chunking’, but I don’t know how to specify the number of chunks or the max chunk size. Advice on how to partition the pak file into smaller files would be highly appreciated.