Just purchased my first Cobra in December at a fairly cheap price, knowing it needed some TLC. Number 7 cylinder has oil leaking down from valves. All other cylinders are good. Can i replace valve stem seals for that cylinder with head in the car? I know there are ways with compressed air etc etc. I know this is a half ass fix but had a suprise when I went to re-seal Diff. So my budget went to that Car has 68,000 miles. Thanks for the help !!