also there is not alot east of 91 until you get to 72 AMC 6. the bird on 89 has some cbn feeds, and a few scrambled channels, the SES bird on 87 has to be very fine tuned to get the retro mix of 30 or so channels, then on 83 the signal is quite weak, for me anyways.. I get the P.A network at around 45 pct and there are not many feeds on that sat, Simon Bolivar has 8-10 channels.
I am a perfectionist so I would still work on the dish to get it tracking properly, however if you are not a perfectionist then the only thing you are missing really are the rtv mix on 87.
Best thing to do is to swing down to the 139 sat and have a way to view signal strength, if you push up on the dish and your signal gets higher that means you are low so rotate the mount to the west a hair, do not change elevation at all! If vice versa and your signal gets better when you push down which I am sure is the case here then you are high in the arc and you need to move the dish eastwards.
Thats what worked for me to get my signal work. A big mistake is when you change the elevation. that will not fix anything unless you are a little low or high on both ends of the arc.