Please, God, tell me it isn't. I just went through three days of hell totally revamping the top end in my '68. Got it all put back together finally but the damn thing just wouldn't start, kept trying to fire but just wouldn't catch. I tested compression on #2 and got 60 lbs, and that's when it hit me, I don't think I properly aligned the new timing set! Please, please, please tell me I am not going to have to tear this whole thing apart again to replace valves.