there's a guide at xda dealing with that, but only the hd7 (the overseas model is only 8gb, usa is 16gb).....i have a brand new 2 class sandisk 32gb card (2 class and sandisk being the only ones you can do this with without corrupting the phone)....i might really try this..
! here's the thread, might be one for the tp7 soon
http://forum.xda-developers.com/showthread.php?t=883582