From what I have researched the basic modification would require opening vents at the top of the motor cover (either drilled holes or lines), lifting the machine on a stand and adding an extra fan at the bottom.
I already have a fan from an old video card with it's own 12V 0.15amps that I will use for cooling. While I get a hold of cacao beans I will try making gianduja with some nuts this weekend.
just keep the the whole engine cool all the time and that should make the work. if something brakes (belt or other moving parts) change them for something more resistant.
just make sure to not overheat the electric motor!if you use cocoabeans just crush them and add bit at time, be patience and add ingredients slowly otherwise will block and you have to remove everything and start from scratch again.
Good luck and have fun!!!