If you can match the old lifters with the same lobes then they don't need to be refaced. I did this on a 360, reused a Lunati HFT cam and lifters I had been running in a 318 and they were fine. I put 35k miles on that 360 and the lifters and lobes still looked fine when I had to tear it down due to busting a ring land. That cam and lifter set probably had 50k miles in total being run in 2 different engines and it was a modern Voodoo grind to boot, not exactly slow ramps...