afni.nimh.nih.gov

Hi,
I have 4 sets of anatomical data and i want to create one volume, treating each anatomical set as a time point.
So test1+orig test2+orig...test4_orig -> test+orig[3d+t:4]

I routinely use the 'glueto' option in 3dbucket to get sets of the type [fbuc:4], but dont know how to get [3d+t:4]
How do i create the desired volume?
Thanks!
Shantanu