🚀 go-pugleaf

Could someone tell me how to specify the word on which to sync
an MFM read using the TD_RAWREAD command?
 
I know you have to set the indexsync bit in the flags offset,
but I cant figure out where to put the sync word.  Ive tried
putting it directly into the $dff07e register, but that doesnt
work.  I know my code works because I can switch the command to
TD_READ and it works fine, but its in DOS format. I need raw
MFM.. I know its not syncing correctly because I get completely
different data each time I try the MFM read..   Into what 
structure or what location should I put my sync word?
 
Thanks tremendously,
  Jim