Hello, my name is***** and I have over 20 years of experience as a veterinarian. I understand that Tuffy has severe dental disease and needs some extractions and I understand that your regular veterinarian is beyond your means financially now.
It sounds like Tuffy is well beyond brushing at this point.
Your other option is to contact your local shelter or humane society and see if they run a low cost clinic or know of one in your area.
If not here is a web-page that lists some that may be able to help:
Other sources of help can be found here: http://speakingforspot.com/?p=Financial%20Assistance%20for%20Veterinary%20Care
It may take a while to find a source of help for Tuffy, so I am glad to hear that he is on antibiotics now, that will help at least keep the infection down in the meantime.
It may be helpful too to use an oral rinse with Chlorhexidene such as CET rinse to help control mouth bacteria. Here is a link to show you the product: http://www.1800petmeds.com/C.+E.+T.+0.12%25+Chlorhexidine+Rinse-prod10592.html
Best of luck with Tuffy, please let me know if you have any further questions.