The third lottery was for the ketores [incense], which was only for cohanim who never brought the ketores before.

The fourth lottery was for bringing the limbs from the ramp to the mizbeiach.

Yuma 2:5

The korban tamid was brought with 6 cohanim. Four for each of the limbs and one each for the minchas chavitim and wine. On Succos they would add another cohein for the pouring of the water. For the mincha tamid they added 2 cohanim for putting on the wood.