I'm looking to build a Reverse trike starting sunday when some parts come.

If i do it, can i still ride it on my full UK motorbike licence?(passed 2008 before the new one) Will it still be classed as a trike? or a 3 wheeled car since its 2 wheels at the front.

It will still be under the 450kg limit.

The Piaggio MP3 scooter is a 3 wheeler with two wheels at the front, that's just ridden on a bike licence.

Rules for 3 wheelers changed in January for new drivers to require a motorbike license us "older" drivers can still drive them on car licenses apparently.

http://www.telegraph.co.uk/motoring/motorbikes/10043638/Changes-to-the-three-wheeler-licence.html

Looks like i will be good Either way then. Cheers.

That new ruling makes no sense, mind you makes as much sense as the old one. You now need a bike licence to drive something that drives like car if you have a car licence, wheras you used to be able to drive a car like vehicle if you could ride a motorbike???
The worlds gone nuts.
Cheers,
Bob