I have to disagree - the ballast drawing is correct for this set. It does show pin 6 as the common tie point and capacitors are used in place of resistors to eliminate the waste heat.
The original 105s are too small if you add up all the tube filament voltages (75.4 and 81.7) you get around 140 and 120 for the resistors. I imagine Motorola was stuck using the same ballast as earlier models with different tube line ups. When I crunched the numbers though I found that 8.2uF is a better choice than 10uF. Here's the original discussion thread:
http://videokarma.org/showthread.php?t=249434
Also, I've actually reduced the 33 ohm resistor to boost the B+ in some sets to make them run better.
The grille cloth is woven plastic and can be cleaned with a mild detergent and a sponge or cloth. I haven't bothered trying to flatten one out. Possibly pressure and heat would work but I don't think it's worth the risk.
I've been using Novus #2 follow by Meguiars Cleaner or Tech wax lately with good results. Only wet sand as an absolutely last ditch effort.
Good luck!