A potential sweet and satisfying revenge...Your thoughts??

OK...my paramour, Thelma (pronounced El-mah) has stepped out on me with non other than our local funeral director, Casey Culligan, the sleaze bag. Thelma, my white trailer trash g/f with dyed blonde hair and no teeth---another words, a Goddess...has been up to no good with this speck of humanity in the back seat of the rusted out '67 Pontiac Parisenne that I bought for her---the vehicle that is sitting on cylinder blocks as my trembling hands write this in jealous fury. Anyway....Thelma has this habit of using the metal springs that stick out the upholestry to "pleasure" her lover. I know from experience. So---a few moments ago, I snuck into the trailer park and put some fine traces of rat poison all over the metal springs. This will definetly be a sore spot for the funeral director. Is there any other vengeful acts I can perpetrate?? Your thoughts and advice????