I would suggest you PM me with your email and phone number and I can help you through this. I build lots of these systems, and am pretty familiar with this machine. If you do not mind sending me the parts, I can get you a working system. It is possible to use the current control board (that I would send to you reconfigured), but we would still have the issue of programming the VFD. So it may be easier to use a single relay design and provide additional controls.
What I am suggesting is you can unbolt the control system box with the two 6 mm Allen screws on either side of the control board and remove it. Also remove the front control panel with the 4 screws. If you send the WJ200 VFD, the control box housing (NOT the current system board inside it) and the front control panel with switches, I can build a new system for you and program the VFD. You should just have to bolt the box to your machine and mount the front panel, connect power to the VFD and the motor lead. All the cables and switches will be mounted, so there should be no need for figuring it out and I will tune the VFD to the stock 3 phase motor. It takes me a while to get the parts in, so probably be 3 weeks once I get the system, I have a couple of other systems I am working on. We can go over the details, if you want other features, I would use the single relay design that uses the VFD power supply. I would do the speed control, 2 braking rates, jog forward, E-Stop if that works for you. I would need to replace the E-Stop switch with a 24VDC LED lighted one, I will use your current Jog button, add a braking rate switch and I have a speed pot that I will need to make an adapter to fit your panel. If you have a 24V light I will need to know that. Lets see what can be done. You would need to purchase a braking resister, I will provide links, they have 2 wires to connect.
You need to think where you want the VFD to be mounted. I am trying to keep it as simple as possible so you do not need to connect/disconnect any wires, so you could mount it on the wall behind the VFD, or the back or side of the headstock cabinet with a shield over the top of the VFD about 2-3 inches above it. The VFD power in can be configured for a plug or a direct connect, but should be on a 30A 240VAC breaker.