This mod requires no drilling or other permanent modification or alteration of the printer.
There is no limitation of or intrusion into the working envelope of the printer.
The heaters mount on the spool rails via clamps, so you can set them to any location that you prefer.
You can mount the remote heaters on either rail, so you can retain use of the lower reel locations if desired.
I always print directly from a reel dryer/dispenser, so I used the lower rail for cable management for now.
You can route the power cables for the heaters through the printer's cable duct and out the back or down to the printer cart.
Hardware:
The mount clamp inserts are M3 6mm and the screws are M3 10mm socket head.
The mount saddle inserts are M3 4mm and the screws are M3 8mm socket head.
The shelf clamp inserts are M3 6mm and the screws are M3 10mm socket head.
The shelf attaches to the printer hinge side with M4 8mm button head cap screws.
There is a cutout in the shelf support to provide finger clearance for these screws:
Files:
The step and stl files are here:
https://www.amboymedia.com/cad/raise3d-pro2-plus-tordsen-heater.zip
Heaters:
Thordsen 3D site is here:
https://thordsen3d.com/
I have no affiliation with Thordsen 3D.
Their customer service has been exemplary so far.