Hi!
Yes it's totally possible! You can see mine running here:
http://www.youtube.com/watch?v=ZdfUo0-vkmsI recommend as I have used to put small feet to raise the A1200 slightly, this will create an airflow underneath, I also put a fan above the BVision, it was quite noisy but quieter solutions are available.
I was using a converted ATX PSU and put extra Power into the Floppy connector, this helps ensure the BVision get's enough power.
You can do a tidier internal install taking more time, the only thing to bare in mind is during prolonged use is still gets pretty warm, if you put a separate fan on your 68040 this might help, look for a low profile chipset style cooler with integral fan and use adhesive transfer tape to secure.
Good luck with your project.
Steve.