What size axles should I run?

[kafercup55]

I'm coming from the watercooled VW scene and building a German-looker that's more performance than look, and I have a quick question re: axle sizing.

The car is a 77 standard with a completely rebuilt IRS chassis. I have a KCR ProStreet Tranny on the way, and CB Performance disc brakes on all 4 corners. The wheels will be RH ZW1's in a 17x8 and 17x10 setup with an ET of 35 after adapters are used. What size axles should I use here? I'm not worried about the wheels because I already have to replace the stock fenders with a fiberglass set.

Thanks for any help you could provide.