Speaking from personal experience here, the hardware itself inside the CV1 is vastly different from the DK1, even the DK2, you have to source a DK1 to XXX hardware emulator to get it to work, and even then it's a 50/50 chance it'll work properly. Hawken itself with the -VR command line entry, will start the game in VR mode, but will only work IF a DK1 unit is detected, otherwise it'll just switch back.
You need either modified drivers, or a hardware emulator, the former being easier to find then the latter, and properly set things up and hope it works. Though I will stress you MUST maintain 90fps, no ifs, ands, buts, you MUST maintain 90fps, other wise you're in for a very bad time. Given the poor optimization of Hawken coupled with the high demands of VR, make for giving Hawken VR a monumental challenge. SLI/Crossfire is a must since your min/max/avg frames needs to be at that 90fps sweet spot. I've only used Nvidia GPUs as of late but with testing on an HTC Vive, I can get fully functional VR with 90fps using at least a pair of either, 980 Tis, 1070s, 1080s and Titan X/XP (whichever nomenclature you wanna use).
Though I will warn, Hawken VR has a MAJOR learning curve, the touch controllers are gonna change that even more. Plus it's doubly so if you're going to use a Vive in the future, since motions can be tied to keybinds.
From my own personal experience to get proper VR running you're gonna need system specs as follows.
CPU: i5 6600k- i7 6950X (faster the better since Hawken is DX9 and DX9 is single threaded workloads)
RAM: At least 8GB of ram, 16GB or more would be better
GPU: GTX 980Ti-TitanX(P)/ AMD needs Fury X? SLI/CFX
Rift USB: 2x USB 3.0 1x USB 2.0 (3x 3.0 if you'll be getting the Rift Touch controllers)
Vive USB: 1x USB 2.0 or better (I use USB 3.1)
To maintain steady framerates, Hawken needs some serious single threaded performance, that's just an inherent flaw of DirectX 9, hopefully in the DirectX 11 update when it gets here will alievate this.
P.S. Small shoutout to Reloaded, can we pretty please get any kind of news if the VR side of Hawken is being worked on, and a rough idea of if/when we expect proper Vive/Rift consumer unit support or are you just gonna drop the VR capabilities(Playstation can benefit with their Playstation VR headset too)?