Here's a thread on a 4runner forum that has some good tips, especially about inhaling the cleaner.
http://www.toyota-4runner.org/3rd-ge...aning-maf.html
Other things I've read say to be extremely cautious about damaging the fragile wires. They're essentially like light bulb filaments. Don't touch them with anything but the cleaning spray, no qtips, etc. Be careful not to drop the unit.
Page SF-33 of the 1MZ-FE half of the "SFI* (Sequential Fuel Injection)" section of the manual
http://www.camrystuff.com/index.php?page=Gen4_Manuals
shows where it's located, how it comes off, and how to test it.
That's all I know. We don't have them on the 4-cyl.