Comin down to a money crunch

If built right would the 8.8 not hold up to this configuration it is said it is as strong as an 8.75 or a 12 bolt

Who says an 8.8 is as strong as a 8.75"?

from everything I've read their fairly decent rearends but not nearly strong enough to handle 820 hp. For that matter an 8-3/4 better be maxed out to handle power like that. Plus I hope your running an R3 or better block with that much power.