I drilled a big hole in my floor:
Then filled it:
Spent a ridiculous amount of time getting the fuel line attached to the aux port on the tank without dropping or lowering it (see the Webasto fuel line thread for details), but plumbing went smoothly and quickly otherwise. Still need to do final wiring and some minor things, but I made some temporary hookups so I could fire it up tonight.
Basking in 70deg warmth with temps below freezing outside made it all worth it!