Raised white letter tire recommendation

The rebuild of our 1967 Barracuda ‘Vert Formula S is progressing. Family decided they wanted white letter tires, so I am looking for brand and size recommendations.

Here’s the car’s stats:
1967 Barracuda Formula S ‘Vert rebuilt suspension, new torsion bars and rear springs.
Driver and cruiser, not a racer.
Formula S engine and trans long gone.
Rebuilt, “Plain Jane” ‘78 318 and rebuilt ‘75 Volare 904.
Rebuilt 7.25, original ring gear worn out, replaced with 3.55.
Power steering and Kelsey-Hayes disc brakes.
14” SBP Ralley Wheels. 5.5” inside the lips of the rim.

With all this in mind, what size tires would you recommend to;
1. Not rub anywhere.
2. Not severely alter speedometer reading.
3. Best RPM/mpg for driver/cruiser with 3.55 ring gear.
4. White letter.

Thanks in advance for your input.