My fiancee and I are planning to sell our 1967 mustang
. It is a straight six. The interior is in pretty good shape a couple of tears all still original. The exterior was repainted a few years ago using factory color. The top is the hard top but its black viynl, it needs replaced and it also needs a new trunk key since my fiancee lost the keys and only had the ignition/door key replaced. We are replacing a blown head gasket prior to selling. Any idea on how much it is worth?