OK, so im trying to do a simple lifter swap. D.Hearne sent me lifters (thx). I pull it all apart....roller 5.0 carb'd. Pull the lifters out and, ta-da...the first and last lifter on each side wont come out without pulling the heads (not doing that on my short vacation)...so, I decide no big deal, i'll switch the lifters I can get to and hope it fixes my ticking problem on the right side...so I pull the lifters out that I can, and go to pop the new ones in and, nope, they wont go in. The lifters look IDENTICAL! The new ones will get the roller tip in then nothing...I tried oiling them tons to slip em in, still nothing....so i dunno what the problem is here? I tried one of the old ones to see if maybe I was just putting them in at a weird angle of something, but nope, they just drop right in....so....whats the deal? any ideas?