Engine Centerline - Dimension

As everyone knows all info on the internet is 100% accurate, but just in case the one piece I am trying to find out thought I would ask and see if someone here knows for sure. My 69 Dart has a 72 360 installed, it had what looks like the solid Moroso mounts in it when I got it and some cheapo headers. I am going back to the rubber biscuit mount and some Dougs headers (not the Blues Brothers one) and engine seems low. TTI gives some dimensions to use but was curious if they are actually valid. centerline from top of K member is noted as 5 1/4, with tolerances I could handle a little off but mine is close to 5/8 - 3/4 off from that, I ordered the truck biscuits which might take care of my queery but is there a true spot I should be looking for or should I just make sure the fan doesn't hit and let it go? my headers hit the torsion bar on the driver side, I have no issue slamming it with a hammer and even after tonight raising or lowering and checking it isn't going to take care of the clearance so there will be wacking.