Well, I've actually done it thanks in large part to Mike Gerber's advice on how to get the bottom part of the panel off. I took photos in case I could figure out the Photobucket process Whip Cracker was referring to but I don't think I could do any better than the link supplied by MIK1989. Those pics had arrow and pointers and everything! (And I am not familiar with Photobucket)
Here's a couple of tidbits that might prove helpful to anyone facing this task in the future:
1. The Heater/AC lamps are EWG203; Toyota part no. 90069-98004. You will need 2 of them and they are hard to find (or were for me). Luckily, I'm in a large enough city with 3 Toyota dealerships, but only one had 2 of them (of course the dealership across town.) I paid $4.17 apiece, although the guy said the MSRP is about $6.50.
I also found the EWG203 lamp on line from Mouser but while they were cheaper, shipping cost more than the bulb.
http://www.mouser.com But since I had the whole unit taken apart, I was impatient to get the bulbs locally if possible.
2. My burnt out bulbs had little green rubber caps (another forum referred to them as mini-condoms). The bulbs I bought didn't have the caps so you need to take them off the burnt out bulbs and transfer them. I guess that mutes the brightness on the knobs.
3. To remove the faceplate to the heater unit to get to the bulbs, you will need to remove the three knobs as well as the knob to the vent arm. Be careful not to lose the thin little plastic/lucite arm inside the vent knob. I'm not sure how important it is to reattaching that knob; it seems to give it some stability.
4. FWIW, I also replaced the ashtray bulb. That was part no. 90981-14011 and cost me about $2.49. The guy acted as if that was a more common bulb to get ahold of.
5. I also found that to get the proper leverage on pulling out the bottom part of the panel trim, I turned on the car and put the gear shift into D-1. Just not a lot of room to maneuver between the gear shift in "PARK" and the panel. You'll also need the room when replacing the bulbs.
6. To get the panel trim completely off, you will need to remove two plugs from the cigarette lighter assembly, The top one you press a latch underneath and pull out. The other is a two prong, right-angled female plug you pull away from the male prongs. Pretty easy, even for me.
I hope these tips help and again my thanks to those who took the time to reply. It helped a lot.