How to identify a non lockup A999 transmission with pics!

if you are really looking for a quick 904-998/999 callout at the junkyard, I believe the ribbing over the bulge in the exterior of the case is an indicator too. my 904/6 has no ribs over the passenger side servo at the tailshaft seam while my non lock up 998/999 has 2 distinct ribs bracketing the servo bump.