70 dart 470 ci drag car build.

Well, timing chains suck when they're used.
I had newbomb over to show me a different method of getting the cam in. It came out to 108.5 icl. We didn't move it from the last time I had 106.75 so it's just not very accurate but it's close and it's getting sent as is.
Next year I'll treat the engine to a milodon gear drive.
Sorry no pictures, just words.
What are the two methods used and how do they differ?