If it were my dime, the cost to acquire & install an 8 3/4" would allow me to sleep better at night. Relatively cheap insurance. I'm sure someone has an 8 1/4" that their running 500 lb ft through on 10" slicks, but that's the exception, not the rule. While looking online, the cost of doing an 8 3/4" really isn't much more than doing an 8 1/4". All the parts are readily available for either rearend, but there is a lot more strength in the 8 3/4" they did run them behind the HEMI automatics after all!