rusty
you can measure end for end but hard to measure tilt or a twist ie square x and y
(but then that's what rod pins are for:)
seriously OP
let's say your pistons and rods are NOT blueprinted
and you find your deck heights are off end for end
you can always swap the pistons around (keeping the exhaust valve notches in the correct spots) and maybe get them closer
this can adjust for both deck and crank throws being slightly off
let us know what you find out
