I know you mentioned time issues. But in terms of difficulty it is a lot easier than a PF swap. I as well probably others would be happy to help guide you with some instructions if you are willing to give it a shot. I think the best part about Vcabs is the fact you built it.

I see, they had you get a barbone system and now you need to assemble it. That portion would be best helped with youtube videos. Installing the cpu/heat sync is prob the only complicated part as you need cooling compound. The rest, is pretty much plug and play and install os/drivers.

Just to get the ball rolling, some instructables:

You can start with this:

Some instructables for Virtual/Visual Pinball.
http://www.instructables.com/id/Digital-Pinball-Machine/

More instructions on cabinet / Ipac / buttons etc.
http://pinacolada.danielpotter.com/cabinet-parts-guide/step-4-buttons-etc.html

1. Games, you can use Pinball Arcade, Pinball FX and VPForums.org
2. You can use a front end. Many to pick from. One example is Hyperpin
http://www.hyperspin-fe.com/forum/showthread.php?2255-Announcing-HyperPin-Digital-Pinball-Frontend
Another option is Steams Big Picture which is what I use now.
3. You will need a controller board for your buttons. The IPAC, they have released several versions. Ipac3 etc.
http://www.ultimarc.com/ipac1.html

I agree. Steam Big Picture for front end with pinball FX "has movable DMD and portrait mode" Pinball Arcade at least has Portrait and will have cabinet support someday. I would strongly recommend skipping VP, FP since they are a pain to configure and almost all of them are ugly as sin. As well as front ends like Hyperspin, skip that and use steam. Once you get your barebone system put together "use the video I posted above, its a multiple part video. It will show you how to install everything, it's not that complicated. The last thing to do is install the iPac and your buttons and mount the montors/tv's. By sticking with steam only, you will save yourself some major headaches. Editing a VP table or even installing them for the first time is frustrating as hell. It will overwhelm you.

Well, you have a nice rig. Just have to put it together. After you build this you could build an arcade cabinet and use the same computer to run the pinball and the arcade. Since from what you will learn from this project the arcade will be a piece of cake