Have recently acquired an ingersoll/case 80xc. Does not want to run but does sputter and spit. I understand the carb is varnished and needs to be removed to be cleaned, however I do not have a manual to explain how to remove the heat shield from around the muffler to get to the lower bolt to remove the carb. Very bad enginering if you ask me. Any help would be appreciated. Would like to acquire an owners/service manual. THANKS!!!!!!