Yes, it can be done in the drivway but like was said before, you will have to "air up" the cylinder or use the string to hold the valve up in place while you remove the lock keys, retainer and valve spring. I have used an old spark plug and welded one of my air tool fittings onto it and then thread it into the plug hole of the first cylinder and put the airline to it. It's a good idea to pull all of the plugs when you start as it is going to turn the motor over when you put the air to it. You leave the nut on the stud so you can use the manual spring compressor to loosen the lock keys and retainer plate. The new "umbrella seal" should just slip over the valve and slide all the way down. Put everything back together making sure you have the locks in properly (I usually give them a little love tap with a soft hammer to make sure they are seated) let the air out of that cylinder and then onto the next. Not a bad idea to put in a little heavier spring while you are at it. The V-8 springs will fit as well as the seals. Available from the dealer or a good machine shop.
Good Luck
