64 Barracuda - Need Picture & Measurement

Here's a PhotChop of KCOYLE's cuda with a 20" AR Torque Thrust M and a p295/45-20 mounted to it. I'm thinking 20's may be too large for this opening, and may have to go to an 18" rim, or possibly just a smaller series tire. Overall height/width of this combo is 30.5", but going to a 265/45 will reduce the height to 29.4" and will still fit on a 10" wide rim.