[oldman3]

Akeane01, in Pic 1 and 2 are of a 38 Chevy coupe currently in our shop, they had installed an original Mustant II crossmember about 15 years ago. You can see that they had to notch the frame to get the upper A arm to clear the frame.
This top hat was welded level with the frame. Top hat had much smaller amount of slot to adjust the caster an camer. They had no issues with how this set-up drove down the road. They did have us put on tubular uppper and lower control arms, and it will have coil/over shocks.

If you could give us more info on where you got your set-up, I'm sure we can get you headed in the right direction. There are great resources on here...Jim