easier with head off and one of these 250539166678(ebay item#). You can do it with the head on you just need the cylinder your working on to be at tdc and put some rope down the spark plug hole to stop the valves from being bent. There is also a threaded air check valve you can use to keep the the valves closed while compressing the springs and removing the keepers. If you've never done it before best to have someone who has help you.
and off the car 390122555533 Also the seal removing pliers easily made with a welder or bought 350286940010 intall well a deep socket 10/11mm IIRC works or the proper tool found at samstag or the like. HTH's Austin