I changed my coolant last night, basically following the book procedure. I tried it without actually removing the tank (because I have LEDs installed under the tank), but couldn't reach the cap well enough to put coolant in. The tank pivots forward on its mounts if you remove the bolt and disconnect the gas line and vacuum hose from the petcock assembly and the breather hose from the right side, but can only tilt forward so far before the instrument assembly touches the fork. So, I proceeded to disconnect the wires under the right front of the tank beneath the right forward cylinder head shroud, and removed the tank. I didn't actually take it all the way off the bike, but rested it over the battery area, with rolled and bunched towels underneath it. This was stable enough for a short period, although I didn't feel very secure about it. Next time I'll probably disconnect the lights as well and remove the tank entirely.
Not a terribly difficult procedure (at least it wouldn't be if I didn't have the lights installed), but I still wish they would make the filler cap accessible.