Manual Transmission - rear gears and T56

I have a 2002 Z and is a 6sp car. I want to upgrade my rear gears. Stock 3:42s i can cruise at 90mph in 6th gear at 2K rpms.

what will my rpms be at with 3:73s in 6th at 90 mph?

what will my rpms be at with 4:10s in 6th at 90 mph?

Thanks

when i had the stock 3.42's in my m6 SS 90 mph was around 2,000 now with 4.10's i'm around 2,000 at 80 mph but it only lost 1 or 2 mpg on the highway and picked up a little mpg in the city.

http://www.f-body.org/gears/
Use that to caculate the #'s

according to the gears search using 26.1 inch tall tires...
i'll be at 79mph in 6th w/ 410s
and 83mph in 6th w/ 373s