New to this site, and it looks real good ! I have read through the posts and gotten some good ideas, and have a few questions related to my '69 sbc 327. The balancer is a 6 inch and the timing cover is aftermarket with a tab that is for an 8 inch balancer. The original tab was welded on to the cover, so setting the timming is hit or miss. I found a tab for a 6 3/4 to 7 inch balancer, but TDC is way off, and the spacing between degree marks are not the same as the 8 inch balancer. What have you gearheads been doing with this, to be more accurate ? Can I put an 8 inch GM balancer on this crankshaft, which is NOT threaded for a retaining bolt and expect it to stay on ? And just for my learning experience...when people talk about 2 degree advance or 10 degree advance on balancers, does this mean the marks on the balancer are that much from the center of the keyway or just what is meant by this?