You need to make some clarity with your sentencing..
What do you exactly mean by that? you can't get dualboot on sdhc? If that's the case you can make BT3b install onto sdhc and then install windows on the ssd. You then reconfigure lilo/grub to make sure dualboot works. Also you need to set which device has boot priority, I suggest the sdhc and you put either lilo or grub on that partition.I have gotten both OSes to work when on the ssd, but niether of them on the sdhc (I have gotten the live BT3 to work on the sdhc).