Use Yamaha P300 as a controller.

Hello.I have an old Yamaha P300 piano which is I haven't used for years due to the fact that it is weighs a ton and nearly impossible for me to transport,but still works perfect.
Can anyone offer me any advise on if I could remove just the weighed keyboard and whatever else would be needed from the Yamaha case and what I would need to add to this to use as a midi controller for my ipad with igrand and other music apps.
I would be prepared to make a new case for this if it could be done
Thank you.

Rather than dissemble the keybed. Myself would cut down the existing cabinet. You then still have rear connection available.