rough idle when hot 5.3convertible

[Johnscotty22]

Hi there,
My 89 5.3 is running well starts perfectly when cold,slightly rough on tickover,but when i start it when its at temp it starts but is very rough until i rev it a few times then it settles out.
I'm thinking injector couplings/wiring harness
.. all the other ignition components have been replaced..oil pressure perfect..
Any thoughts?
Regards,
Scott