Hello im new to the site. Im restoring a 1991 honda 4 speed 1.5 hatch with mpg in mind. Im going to be swapping the trans for a 5 speed. Can someone please tell me the best 5 speed cable trans I should look for. I see different ratios, splines and lsd. Im mostly interested in mpg. Also would A head swap be worth while? Any info greatly appreciated. Thanks