I am a great fan of demoscene (computer art subculture) since middle school, and hence it was a ritual i had to perform.
For estimating the Elo, I measured 240 automated games against Stockfish Elo levels (1320 to 1600) under fixed depth-5 and some constrained rules, using equal color distribution.
Then converted pooled win/draw/loss scores to Elo through some standard logistic formula with binomial 95% confidence interval.