Grandpere, And for anyone else who may be interested.
My original tires were 8R 75 19.5, and after your advice Grandpere I did a little more research and today I put 245R 70 19.5 on the steering axel. No problem with space or fit. The 245's give me 2 1/2 inches more tread on each tire which equates to 5 inches total. On the rear the 245's were a little too close and we settled on 225R 70 19.5, which will give me 1 1/4 inches more tread on each tire making a total of 5 more inches of tread (its like adding nearly another tire lol).
I drove 75 miles after the new tires were fitted, and the difference is like night and day, No wander and No rutting and No white knuckles, Any change in recorded speed and actual speed will be minimal due to the speedometer cable being attached to the Transmission at the back of the coach which can be calibrated at a later date.
Total cost for the Six tires out the door with national road hazard warrantee was $1382.00. Oh yer the tire are Samson which are apparently made at the same plant as the Michelin equivalent in China and Michelin tires were $480 a piece!!
Samson are also a widely used tire within the trucking industry because of there reliability.
Thanks Grandpere, I owe you a beer.