Dave, you have the right calipers, and everything is normal. Original wheels were never designed to fit over calipers. This is discussed at length in the Brake Conversion thread.
You need either 15" wheels OR 14" that went on disk brakes. The most popular wheel is the Granada/Mustang wheel. Howard Prout made a trip from Canada to test his 'new' 14" Granada wheels on my setup before he started his Squarebird. They fit on mine and they fit on his Squarebird. We both have the same spindles and calipers you have:
This is a 14" X 6" Granada wheel. Howard is holding a tape measure against the back of the spider to measure for back spacing. The front (on the LH side) shows the valve stem hole.
NOTICE, on the bottom of the wheel there is a bulge in the center-right. That is there for caliper clearance.
Squarebirds and '59 Galaxies use the same spindle. Therefore, the caliper bracket is identical. I am using the same Scarebird part on my car as Howard is on his Squarebird.
Notice, the Galaxie is using 15" Cragar SS wheels (to the left). They fit just fine. Howard had just bought a new set of 14" tires so he wanted to stay with 14" rims:
I had run my power disk brakes all summer long before Howard tried his Granada wheels. They probably look identical to yours only older, now:
So, don't grind ANY off your calipers, rest assured you have the correct brackets, and get new wheels designed for disk brakes. I understand the 14" spoked Squarebird wheels fit, too (but they are very expensive).
My '55 Ford Customline came with 15" x 4.5" wheels. For the heck of it I tried one on the Galaxie... it fit. - Dave Dare