I am following you up to this point.
Put the 2.3.4-380 to 2.3.5-418 (or whatever version you require) on your sd-card and apply update using the stock recovery, or download and install the update from your phone settings.
Run Voodoo, Restore Root, Delete Backup
Will voodoo do all this? also where do I find the 2.3.4 to spf. Is there any instructions on how to do the spf. ? i have done it before but its been long time.