ok, you can use dsrd to extract the middle 64-bits (you'll have to mask to 44 bits afterward), use:
srdi outh, t0, 64-44
li temp2, 88-64
srd temp, t0, temp2
dsrd outm, t1, temp2, temp
clrldi outm, outm, 64-44
srdi outl, temp, (64 - 40)