LA360 initial timing too high - are there different timing covers?

OK, on the compression, OP. Yes, it sure sounds this a low CR, wide duration cam situation. AJ makes a very good suggestion to take cranking compression readings.

And yes, if the exhaust lift is that low, then for sure that lifter has leaked down. If you ca, just fire it up for 10-15 seconds and get that lifter pujped up and then shut it down and see what you get.

Also, put the damper at TDC for #1 firing, make a mark on the distributor body directly below the #1 spark tower on the cap, then pull the cap, and see how far off the rotor is from that mark. If it is way off, then the rotor and/or cap may be indexed wrong to the distributor.