AFTER I hinged the flaps and aileron, I noticed when aligning the flaps to the center section of the wing and aligning the aileron to the flap, the aileron does not line up with the wing tip. It is about 1/8 inch higher then the wing tip.

If I align everthing to the wing tip then it will be off at the center section of the wing. Any suggestions? can I get by with this? Where does the difference have the least amount of effect, at the wing tip or center section?

This is the H9 1.50size P51

Sounds like a little wing warp or surface warp. All my plane's have a small amount of this too. H-9 P-51 60 scale is one of them. I think it has to do with many thing's. Wing warp, flap / aileron warp, the position and centering placement of the hinge' (s), heat or cold stretching the coating and causeing warp. I set the outside or wing tip surface's as flush as possible and work toward the fuse. Works for me. I have a GP Stuka with the detached dropped aileron and flaps. They are real fun to get rite.
Good Luck, I'm sure it will work out with a little extra trim.
Just my 2 cents
JWA

Yes, it is definitely more important out at the wingtip, so get it to line up there. I'd line up the inner edge of the flap to the main wing and fly it. It will be fine. My buddy has the same plane and the same result. Once you maiden it and get it trimmed, it will fly great.

Sometimes this can be very easy to fix. More than likely the flap it'self is warped a bit. Take your heat gun and apply heat while bending the flap to align with the wing tip. I had to do this on an Ultrastick and this did the trick in a few seconds. Mine was very easy to fix. Just be careful to not get too much heat in just one area, or you could damage the covering. Keep moving it back and forth over the warped area until you are satisfied that it's aligned.

Hope this helps.

Thanks. I'm pretty sure it's a matter of hinge slots not being centered. I'll align to the wing tips and the flaps will end up being slightly off at the center section.