I've seen 5x114 conversions but is it possible to do a 5x120 on our old hondas? or do I need custom rotors or re-drill the holes on the wheel?

 

It would be all custom since none would be stock.
You would have to get the 5 lug hubs and have them machined to fit.
Then you need a rotor to fit as well as a brake caliper bracket setup that works with the brake rotors.
And then there's the rear .....

 

Yea that's what I thought...it's for a future project just thought I'd ask.