Assuming you have completed the trap calibration as detailed in the DX Engineering New Assembly and High Performance Installation Instructions (pg. 39), the DXE-VMN-1 would be your next step.
The DXE-VMN-1 Vertical Antenna Matching Network is designed to be used as a low impedance matching shunt coil on a resonant vertical. On efficient vertical antenna systems, usually those with many radials, the feedpoint impedance has a resistive value of around 35 ohms at resonance (low reactance). The use of the parallel coil, across the feedpoint, rematches the feedpoint back to 50 ohms for a resulting low SWR. The DXE-VMN-1 may be used for impedance matching on a Hustler BTV series antenna, where the resonance on 80 or 40 meters occurs at a low impedance.