I have seen guys use wheel barrows for the trans hump/firewall.......as crude as it sounds ,it works and looks rather well...........Think of the view looking at the wheel barrow from the front standing on its wood handles.............. I saw the finished product and it looked very nice .......though it would be much cheaper and probably quicker to just buy the pre formed metal one ,if you need metal,if not the fiberglass mold style will get you the correct clearance for your application and let you make the most out of foot room available.