I HAVE USED SHIFT KITS AND HAD GOOD LUCK WITH THEM. BUT FOR THE SAME OR A LITTLE MORE MONEY,AND THE SAME AMOUNT OF WORK,I WOULD RECOMMEND GETTING A NEW VALVE BODY. IF YOU GO FULL MANUAL , BE CAREFUL , SOME KITS MAKE PERMANENT MODS THAT PREVENT YOU FROM BEING ABLE TO CHANGE YOUR MIND LATER. I WOULD RECOMMEND A AUTO/MANUAL VALVEBODY , UNLESS YOUR STRICTLY RACING. THERES A COMPANY YOU CAN GET REAL GOOD PRICES ON HI PERF REBUILD KITS,I'LL FIND IT AND GET BACK WITH YOU. CANT REMEMBER THE NAME . I GOT MINE FROM THEM FOR A TH400 WITH RED EAGLE CLUTCHES,KOLENE STEELS AND FULL GASKET/SEAL KIT FOR $145 PLUS SHIPPING. GOOD LUCK