Inherited vintage Heuer Carrera (3647N) watch need more info /help please :-)

I have inherited my late fathers watch I just wanted to know what type it was etc. I think it’s a carrera but unsure ?
I want to get it serviced as well, I’m in the uk could anyone point me in the right direction ?

Thanks for any help

Rob

Looks like a nice vintage Carrera. I think it's a 3647? I would send it to Abel Court (heuertime.com) for a service. I think the chrono pushers (and potentially the crown?) aren't original, and that bracelet isn't either - I would remove it and replace with a nice leather rally strap before it causes damage to the case. Otherwise, keep it as original as possible save for maybe a replacement crystal.

what a fabulous example.