I extended my bed heater wires (~10A current draw) with silicone 18 awg wire although they are out of the enclosure. They get a bit hotter than ambient (~15 degrees) when printing abs for longer periods and that is ok even for pvc insulated wires.. When the wires will be very close to very hot regions you should oversize the wires a bit since the resistance changes so in my case 14AWG wire is powering the bed inside the enclosure (although 16 would have been just fine really). You should take care that you make good connections when extending wires and if you solder them take care that you dont put high mechanical stress on soldered spot.
Note that your hotend wont be pulling 2A all the time and PID will keep the wires cooler than bang bang mode (same is true for PID bed control).