|The yellow tape says "Heavy"|
Ah, I know what it is:
For my gear head friends, that is a Tremec (Borg Warner) Ford Racing T-5 (Z series) transmission. The regular T5 that comes in the 5.0 L Mustang does not have a high enough torque rating for my little 4.7 L V-8, so I had to go with a beefier model. Plus the racing series has a 2.95:1 first gear, which will be a better match to the rest of my drive train.
Now I'll have to get rid of that shifter on my steering column. Part of me is sad to see it go--but this is a much better solution for a daily driver.