just installed complete dana 60

i just installed a complete dana 60 i had built by dts. it's got 3.54 gears and trac lok. I had the perches moved inward 3/4 inch and 11 inch drums. I could'nt find a complete 8 3/4 drum to drum and decided that the dana was the way to go. However, i've since heard that the dana will lose me horsepower over the 8 3/4. I know it was overkill and pricey but i think i'll be o.k. as far as reliability. It's in the car and looks great. I'm getting a blueprint engines 408" 435hp 500 ftlbs longblock. What do you guys think?