Strangely there are left handed pianos like this one and left handed most things, In the USA they drive left handed cars.
I'm not sure that piano teaching makes you a good guitar teacher. Some skills are transferable, but some concepts don't - for instance a B scale on a piano is awkward, but on a guitar it's the same fingering as any other scale. Position with a guitar is critical and not always easy to achieve. Go and talk to a skilled guitar teacher (we all teach guitar on Mudcat)