Some comments:
Acetone and Benzene are hazardous chemicals, extremely toxic. I would avoid using them, period. Acetone can be absorbed through the skin and get into the body that way. Not sure about benzene. Ethanol and isopropyl alcohol are good cleaners and degreasers and are much safer. However, they too are absorbed through the skin, so wear vinyl or rubber gloves.
After you wash the board, you should unscrew the transistors from the heatsink and clean off the heat conductive grease and replace it, it will be contaminated from the cleaning process.
Do not apply DeOxit to the board. It will leave an oily residue and attract dust, and, well, isn't that what you're trying to clean out in the first place?!:scratch2:
I recommend using distilled water for the rinse, or at least for a final rinse. Tap water contains minerals which you do not want left on the board.
I think this process is fine to do but overkill in most circumstances. Getting the board and all components completely dry is going to be a challenge, and there is a possibility of moving some contaminants into controls and other inaccessible areas. I would reserve this for a unit with heavy buildup of cigarette goo, kitchen grease or other funk.