I went with a solid flat tappet in my car. I use the EDM lifters with the small hole in the bottom for oil to the lobe. I checked all my lifters for rotation before I started it. I use Valvoline racing oil and a zinc additive. No problems at all. I did break the cam in on just the outer springs. With a roller I did not want to worry about valve float if it did not have enough spring pressure and I did not want to worry about a lifter breaking with the high spring pressure they use. I drive my 63 on the street alot and felt the flat tappet would be best for me. Ron