Well, if a program (tedana in this case) is messing up the header info, then, well... the header info might be messed up.

There are two properties here: space and av_space; the latter is the "view" one. For example, the output of this 3dinfo command on the TT_N27 is given here:

3dinfo -prefix -space -av_space /data/REF_TEMPLATES_AFNI/TT_N27+tlrc.
      TT_N27	TLRC	+tlrc

Sounds like you want to change the *space*. I will cite the 3drefit help for both, which are conveniently neighboring:

-view code      Changes the 'view' to be 'code', where the string 'code'
                  is one of 'orig', 'acpc', or 'tlrc'.
               ** WARNING: The program will also change the .HEAD and .BRIK
                  filenames to match.  If the dataset filenames already
                  exist in the '+code' view, then this option will fail.
                  You will have to rename the dataset files before trying
                  to use '-view'.  If you COPY the files and then use
                  '-view', don't forget to use '-newid' as well!
               ** WARNING2: Changing the view without specifying the new 
                  might lead to conflicting information. Consider specifying
                  the space along with -view
  -space spcname  Associates the dataset with a specific template type, e.g.
                  TLRC, MNI, ORIG. The default assumed for +tlrc datasets is
                  'TLRC'. One use for this attribute is to use MNI space
                  coordinates and atlases instead of the default TLRC space.
               ** See WARNING2 for -view option.

... note those WARNING2 comments (which are missing a word, yes: "without specifying the new [space] might lead to conflicting information....", but hopefullyi the meaning is clarified in the next sentence).

See in your 3dinfo output the line:

Template Space:  ORIG

which conflicts with the "view" property. I think your sitation is exactly what is being WARNING2ed against.

Note: I don't think a figure can be "underlayless". It probably just just selecting the offending olay itself, or perhaps some other file in that space (which may not even appear in teh FOV, potentially).

--pt