You need to dissemble the head to lubricate the bearings and Loctite it back together.
Heat did not work for me, not even using a torch and getting the screws red hot. What ended up working for me where T-handle 4mm Allen wrenches. I got the KleinTools from Amazon.
To me, that was the toughest part of the build on the E5's and the E7SE. Before I purchased the T-handle 4mm Allen wrenches, I hurt the palms of my hands trying to get those screws out. Once I purchased the T-handle 4mm Allen wrenches, the first screw came out pretty easily. However, I needed the Grippy to help me get the other screw out.