That'll look great! If you don't cut back the dead/dying DL foliage this fall, you'll be able to see where your DL clumps are... you could just dig holes for the daffs between the clumps, too. I put a lot of daffs into a perennial bed last fall that way... shovel out a big clod of dirt, plant 5 or 6 bulbs in the hole (or just 3 if it's a little scoop of dirt LOL), then put the dirt back down.
