Topband: Spacing for an Inv-L?

[Eric Rosenberg]

The tree climber guy will be coming around soon.  The plan is to have him put in lag screws with pulleys attached on the trunk of the trees (70-90 feet, although I'm not sure that's how he'll be able to go) that hold up either ends of my wire antennas, presently a single OCF (Fritzel) dipole and  a 160m inverted-L.  

My question: since they'll all be in the same vertical plane, how far apart vertically should I have him place the pulleys, assuming I want to add an 80m element to the inv-L. 

How about horizontally, if he can use a throw line from his perch up the tree with a friction saver over the branch?

Thanks in advance,

Eric W3DQ
Washington, DC