On my PO module PO-A "add PO"  it asks for a job # for that PO... say I order a length of steel bar for a total of 20 feet, but I want to use that steel bar for more than one job #.  The PO only asks for 1 job # on that PO.  Therefor I am seeing that I can only enter 1 job number per PO.  Is that correct? Or was there a version update that allows more than 1 job # per PO?

That is correct.  The important reference is the Work Order number entered on each line of the PO.  If none is entered, the PO receipt will go to stock.  If a work order number is entered, then the material will be posted to that work order.  The Job Number entered at the PO Header is simply a reference that can be used for some reports but has nothing to do with the actual posting of the receipt.

Yes, you can use a "P" type purchase order to buy material for a work order and the receipt of that PO will issue the material to the work order.