Hey!

This is my first wheel build! ....so I am going slowly and would like any opinion on choices I have am making.
I weigh 165lbs (75kg) and will use this wheel for hard training on dry days.

I just purchased a NOS '97 Zipp 530 clincher 28 hole rim. I have a Powertap Pro+ hub with the 15mm axle.
The tech at Zipp told me to use Sapim CX - Ray spokes and build with max 85kgf DS and 45-50kgf ND
(rim is older style, '97 with carbon weave). Newer Zipps go 100kgf but not these old ones. The rim has never been laced.

First question: Spoke length 243.1 left, 241.3 is this correct?
I used a few online calculators but got a goofy number of 230 with many trys of the DT Swiss one.
What gives with them? It makes me nervous about my lengths, but I think I need 244mm and 242 Sapims.

The ERD is 525, carefully measured by me. The Powertap site has my hub
diameter as 70mm, flange distance nds left 33.9 and right ds 15.9mm.
2X lacing.

Second question: What is the best choice for nipple? Sapim aluminium Polyax?

Any comments or suggestions? How about my spoke lengths?

cheers
Casey