I have a Cub Cadet 147 with a 48" mower deck. I rebuilt the clutch with new clutch plate and new compression springs and friction disk spring. I went over the two steel surfaces with 80 grit paper. Carefully setup the clutch with the correct setup tool. First time out mowing it started slipping. My grass is thick and lush green this time of year. Is this clutch borderline with a 48" deck? Do I need to upgrade to the clutch used on the later cubs? Seems I need to go slower than I remember so it does not slip. Is there something I am overlooking in the clutch setup?