my wifes 67 convertable with a straight 6 cyl, has been sitting idle for the past 10 years. we wish to get it back on the road but i am concerned about attempting to start it in the event the cylinders are frozen as a result of it's being inactive for so long. any suggestions as to a procedure icould follow to assure i don't damage anything. would adding additives to the cylinders be helpful?? would appreciate any suggestions. thank you. bob