I'll give this a shot. No expert on cams, but I do know something about Y blocks. A couple of things for you...
Did you rebuild the engine, or do you know who did? The reason why I ask is that nearly all Y block pistons have a very low compression height, and a low deck height in terms of where the piston top ends up in the bore....and they nearly all are wildly optimistic in terms of rated compression. It normally takes a healthy cut off the block deck, and the heads, for that matter, in order to actually reach whatever rated compression the piston maker lists.
What I'm getting at is that, if you haven't actually done the math, so to speak, you likely have much less compression than 9:1, even with the .060 overbore,... which will make a difference as to cam selection.
Another thing to look at- although much less common- is that occasionally, guys will run across the HD292 from the '61-'64 heavy trucks. These are considered desirable because of the steel cranks and slightly heavier main webs. What is not commonly known, however, is that they use shorter rods & different pistons...and those pistons have a taller compression height & are not available nowadays. If a regular 292 piston is used, it sits waaay down in the hole at TDC. I've seen this a couple of times...the engine ends up around 7:1.
Not doubting your skills if you put it together, just mentioning a couple of areas to look at.
In terms of your original question
, no, lobe separation & lobe center are not the same thing. Lobe separation refers to the distance between the intake lobe centerline & the exhaust lobe centerline. Can't physically change it. The lobe centerline is an imaginary line that goes through the cam's center axis (from front to back), through the point of max lift on the lobe.
You can move the centerline's relationship to other things around, by advancing or retarding the cam.