Martin,
Here are some computer results for you.
I agree with JoeH's comments about computer vs street - it's important to be able to predict et's BEFORE you go to the strip, that is one way to build some trust. Usually I like to have a 60ft time to feed the computer - 60ft is very hard to computer-predict - at least for me. After that, if the engine is well-tuned, it is a little more accurate.

Anyway for your 63 Nova (I have 2 of em myself!), and with the same 3 cams/engines as above, I got this for your 63 Nova Wagon, assuming all the 200 lb extra on the rear helps the wagon hook up:

Stock cam:
Torq 241 at 3100
Power 178 at 4100
2.22 60ft
10.19 at 68.6 1/8mile
16.05 at 84.6 1/4mile

Comp 240H:
Torq 243 at 3400
Power 196 at 4500
2.22
10.02 at 71.1
15.72 at 86.4

Comp 260H:
Torq 240 at 3700
Power 207 at 4800
2.27
10.00 at 71.4
15.61 at 87.3

Since you mentioned mileage I'd pick the 240H (or the PAW/SSI one, similear). The 260H might be more fun but computed slower 60ft - a hint about mileage perhaps - but, any of these compared to stock should be a big help.

Hey, drive all the way to Sac Raceway and post a before & after run! That's only 400 miles or so round trip!