The major issue is the rear truck design as that's the primary driving truck. I didn't move the tach, I really didn't want the front truck controlling the traction as most of the traction is in the rear when moving forward. My fixes were making sure the small wheels were free-rolling, lubing the arm that rides along the chassis, and forming it so that the small wheels didn't hop out of the rails, but also didn't bear most of the weight and result in loss of traction. After tweaking that, I was able to pull all the cars.
As for the regulators, I stick them to the ceiling of the cars with double-sided foam tape. I fold the regulator tab, and even looking up from slightly below window level, you just see the corner of the regulator. I position them between the window posts to minimize the ability to see them as well.
