solfly

ok so i have this Z6 that im getting ready to build
the motor had spun a rod bearing and the crank is toast
i got another crank but i think its been turned, not sure yet
i can buy a complete A6 for $100 from a buddy which has never been opened so i know the crank is stock
if i can figure out if the crank i got has been turned then ill go from there
if it hasnt obviously ill buy bearings and run it
if it has then i need a crank
so i would then buy the A6
if i buy the A6 should i just use the A6 complete bottom end and mini me it
or should i just use the A6 crank in the Z6 block
i havent ordered any of my internals yet
im going to run SRP pistons and TT rods

also with aftermarket rods how do i determine which rod bearings to use?