Interesting discussion. I wondered further; with gas at ~6.2 pounds per gallon (ambient temp. dependent), a full 42 gallon tank puts 260+ pounds behind the rear axle.
Think
OVERSTEER.
Then consider the change in handling as the load burns off. Put this on 8.5" wide F'stones or G'years of the day and Bondo, Miles, Gurney et al look like genuine he-men to wrestle that. Especially like in the Targa or other endurance races.
#3170-Bruce, can you give some insight?