Your indicator lacks the accuracy needed to check for good enough for a bore.
Piston to wall clearances are typically .0025-.005. An error of .001 would be as little as 20% error, likely much more. Non critical tolerances are typically 10% or less. Precision are 1-5%.
This is a fools errand. It's been tried. The drawbacks, shortcomings and failures are documented, known, and avoidable. There is nothing to be learned or gained by doing a shitty job unless you start a YouTube channel alongside it.
