Like damoroso mentioned above
Back in 2003 :eek I changed out all my dash and console bulbs with 5 Watt bulbs. I got them from Kragens the number for their 5 Watt Bulbs is/was #2825.
Since I had it all apart, I used some Aluminum Foil and lined the plastic around the entire dash lighting area before installing the new bulbs and putting the tach and speedo back together. I know of a couple of fellow 81 owners that spay painted the entire area with a bright white paint. I just couldn't bring myself to paint the area. The area is a blue-ish color and I figure if I didn't like the foil I could always remove it
Well that was 7 years ago and I haven't had the dash apart since
I noticed a difference at night with the brightness, now I can actually read the trip mileage
but it still is not as bright as todays car dash lighting ...
As I recall it was not that hard to do, I don't remember lower the steering column or any bad memories from the ordeal, so it must of went fairly smooth. I tend to remember the pita things I've done, and hope not to have to repeat them :dance... like getting the air/heater/vent control out and rebuilding it... ONCE was enough ...
Good luck, just take your time and do not muscle it, finesse needs to be the word of the day... That day
Bud