Historic racing is not for the faint of heart or shallow of pocket therefore, for most of us it is a spectator sport only. With the proliferation of today's comparatively inexpensive video equipment it is easier to go along for the ride and you never have to strap on a helmet.
This YouTube video from last year invites you to take part in a ride at the glorious Spa-Francorchamps circuit in Belgium with driver Marc Campfield. The Austin Healey 3000 he is pedaling is indecently fast - note the Jaguar E-Types and Porsche 911s being left for dead. If you listen carefully you can hear him clicking in and out of overdrive around the course.
You'll need 18 plus minutes to watch the entire video but - trust me - the soundtrack is worth it.