Mopar R3 Block

Hello Guys and Gals. I have the opportunity to purchase a new never ground on R3 engine block tomorrow. I'm low on time to do adequate research on my own. I am looking for a HD block to build a large street engine out of for my 67 Cuda. I do NOT know what to look for and would appreciate any input and insight as to what the differences are. It is said to be a std bore and std lifter angle. Are all 59 degree blocks 9.6"? Is that what I want for a street engine running victor heads? If I buy this I will be selling my 70 std bore 340 block. Thanks in advance for the help folks.
I found this tell all about the blocks:
How to Build Mopar Engines for Performance: The Block Guide - Mopar DiY
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