use grease to hold them

 

are the heads still on the motor? I was under the impression they aren't. Take the spring and put the retainer on it and use the screw compressor to compress the spring as much as you can. Slide the valve in place and push up on it with one hand. Place the spring over the valve stem and put the keepers in there. Slowly start un compressing the spring. The keepers should catch on the end of the valve stem and hold the spring in place. I don't really understand what problem you are having. Maybe if this procedure don't work, give better details on what you are doing.

 

the heads are on the car. i am compressing the spring on or off the car (i tried both) when down sliding the keepers in, letting compressor off slowly. then they pop off or one comes off and the other stays on

 

faded93bird i sent you a pm with my phone number. an extra hand would be awesome