What do you mean by brute force, exactly? There are far too many possible letter combinations to just check each one.
As I pointed out elsewhere in this thread, you don't need to check all 26^8 possibilities since order of letters doesn't matter. That leaves 13_884_156 possible 8 letter combinations. Since I am using a specific dictionary and no word allows a single letter to repeat more than 5 times, I can further reduce that down to 12_461_993. Since my word list contains 40,933 words, that means I am up to 510_106_759_469 checks. In order to finish in under 24 hours, I will need to be able to do 5.9 million checks per second. I hope my C skills are up for the challenge (stay tuned).