Actually, the probes we sell have 6' of wire on them always, but we do sell K and J type extension wire if you need longer. If you need shorter, they can be cut.
If you're using SkyView, we'd prefer you put the EMS module near the engine (but not on the engine side of the firewall), so if you have a pusher you put the module in the back instead of running all the EGT/CHT's up to the front with long wire.