5-speed manual options

[hotrodchev]

Looking for some advice & comments. I have a '70 Nova SS that I'm preparing to restore and I plan to run a big block 454 with approx. 500 H.P. and a 12-bolt 4:11 posi rearend. What I'm hoping to achieve is to build a stock appearing, streetable car that will cruise up and down the freeway at 75-80 MPH, but will also handle the torque of the big block if I decide to take it down the 1/4 mile every now and then. The question is, what are my options for replacing the existing M-21 4-speed with? Can anyone tell me the pro's and con's of switching to a Doug Nash 5-speed transmission? Any other manual options I should consider?

Thanks in advance.
Tim
"Hotrodchev"