5,000. thats where i shift with mine, but i have an off road H and flowmaster catback. if i shift any later than about 5 it just falls on its face . i ran a 14.6 shifting at 5 and a 14.9 shifting at 5500. with the same 60 foot.
Before my headswap, my car felt like it just gave up around 5000. It would keep reving to 6K, but it did no good because it would just quit pulling. So I'd say 5000-5200 for a shift point.
I'm shifting between 5,800 & 6,000. BUT, I still need a little more practice with the 4.10's, and some DR's. With 4.10's your shift points come a lot sooner. IF you hook up, you better be ready to shift real quick. If you don't, you gotta get off the gas real quick. You guys know what I'm talkin about. It's A LOT different running a car with taller gears than the stockers. I was pissed 3 weeks ago at the track. I was 1 round away from the $ round when I didn't hook up out of the hole. Nothing like a little REV LIMITER for everyone to hear at the line. Oh well, can't expect a whole lot out of those stock $hitty GoodYears.
I was clued into this back when my car was still stock and immediately dropped 2 - 3 tenths from anyhing else I tried. After a dyno session I plugged the resulting values into a couple of shift-point calculators and it was pretty much spot-on. Give it a try.