Boost particles generated by GPS

I’m new to Geant4 and working on a collider experiment. I’d like to ask a question about boosting particles.
The generated particles distribute uniformly under C.M.S coordinate system, but there is a boost from C.M.S coordinate system to lab coordinate system. This can be easily done with HepMC, but I wonder if it’s easy to boost particles generated by General Particle Source, as GPS is much easier to use.
Thank you!