using the ls block is kinda pointless if you want to make serious serious power. if your just planning on something for the street that wont feer a mustang than save the money and get a turbo kit... dont even worry about switching out the head for b16. just turbo what you have and maybe replace the internals and valves and stuff if funds allow.. that will give you nice power for probably the same price as stripping and rebuilding and adding a new head... plus it will give you more power and potential