Sounds like you are having similar problems to what I had a while ago. Only real suggesstion I have is tweak, tweak, and then tweak some more til you get everything. I spent almost two full days on a three day weekend several months back going out and tweaking the dish... I finally figured out that my problem was tied to the pole slipping just a fraction out of plumb so ended up using some copper wire and screws to tighten the pole to the roof with support wires. Your problem sounds more like elevation may be off just a fraction of an inch or millimeter or two?
When teaking, I usually tweak True South first, then jump over the g10 and tweak there to get good strong signals on the weaker tps, then jump around the arc and test out 31w, and everything from 31w to 148...
When teaking, when I get on the arc, but off just a fraction of an inch g10 signals that usually run 99 percent are running 45-60ish and weaker signals don't show up at all. Final tweaks to get that extra little bump usually requre manually moving the lnb without adjusting any bolts... just barely bump the lnb, wait for the thing to stop bouncing if it is, and see what signal is... slowly move left, right up down, etc. If you find you are too low, redo elevation bolt and redo all the hand stuff over, and over til it's just right. Once I do all of that, it's good to go, but wind still can kick me off a few degrees. If I know I'm on the arc but wind's messed things up, I just tweak in the receiver Usals setting... for instance right now I know that I'm roughly 3.5 degrees off, so 123w is actually pointed at 120.5 degrees west in usals... and I have all satellites on the arc doing that sort of thing. Pain to manually change those few degrees, but I know the signals strong enough and just right on the arc that it's easier to do that than go out and fiddle with hand tweaking more at the moment.