Good Morning! 
This is one of my two Reo Grand.
I have decided to sacrifice this Reo to do my experiment: put a DNA20 inside the Reo.
I thought it was a good idea but I was not sure of the result.
The dremel as a single instrument, an old dna 20 to take measurements and will be the way to digging to make the most of the limited space available inside the Reo Grand.
Measures are taken, fit perfect!
Now the faithful friend dremel prepares the space to accommodate the display next to the bottle:
Got it! This was perhaps the most delicate operation ...
Now the part that amused me: where I put the keys to the activation and regulation of the circuit? Here is the solution I propose: hide the switches behind the carter:
Et Voilà: the adjustment is made by turning the key of the Reo to the right to increase the Wattage and to the left to decrease, the activation is normally done by pressing the key down.
This short video illustrates how the adjustment of the Wattage takes place:
With a little patience and luck, everything works very well and and my Reo has a new life.
I apologize for my poor English, and I wish you happy vaping!
This is one of my two Reo Grand.
I have decided to sacrifice this Reo to do my experiment: put a DNA20 inside the Reo.
I thought it was a good idea but I was not sure of the result.

The dremel as a single instrument, an old dna 20 to take measurements and will be the way to digging to make the most of the limited space available inside the Reo Grand.

Measures are taken, fit perfect!

Now the faithful friend dremel prepares the space to accommodate the display next to the bottle:

Got it! This was perhaps the most delicate operation ...

Now the part that amused me: where I put the keys to the activation and regulation of the circuit? Here is the solution I propose: hide the switches behind the carter:

Et Voilà: the adjustment is made by turning the key of the Reo to the right to increase the Wattage and to the left to decrease, the activation is normally done by pressing the key down.

This short video illustrates how the adjustment of the Wattage takes place:
With a little patience and luck, everything works very well and and my Reo has a new life.
I apologize for my poor English, and I wish you happy vaping!