Ok so I have a 2000 f150 5.4 4x4. 3rd and 4th stopped working tranny would neutral out. After a lot of research and testing the symptoms pointed to burned out direct clutches all solenoids tested fine accumulators fine also except a broken 1-2 spring which isn't bad since you can remove the bottom one anyways for better shifting. Bad direct clutch pack means a full rebuild. So I started to tear the transmission down when I got to the direct clutch drum I noticed the splines that the stub/direct Input shaft inserted into on the direct drum are completely stripped. This, not the clutches is the reason for the lack of 3-4 gears. I looked over the other clutches in all clutch packs they look good actually I can still see the writing on them. To me it looks like the tranny may have been recently rebuilt (just bought truck) . So my question is should I just replace the direct clutch drum (60 bucks). Or since I have it tore down go ahead and rebuild it (390 bucks) even though the clutches seem to be still look very good? Or send the kit back (it has a valve body mod if I send it back I'm going to buy a valve body mod Which would save me 270 dollars?

thanks