3/4 drill or hole saw?

i'd use some quality USA made cobalt bits in conjunction with some cutting fluid. start small (~1/16) and work your way up to 1/4 (i think this is the size of the pilot bit in the hole saw) in increments of 1/16-1/8. switch to a 3/4 hole saw at this point (a quality 3/4 cobalt bit is buck$, and most won't fit in a standard 3/8 chuck - shank is 1/2).

also go at the slowest speed possible when drilling. on a drill press ideally you want to get it as low as possible but i've drilled plate pretty cleanly with a press that goes down to about 300 rpm. even slower better but sometimes not always possible.

all said, it might still be cheaper to just pay someone to do it. quality morse brand cobalt bits in the 1/16-1/4 size go for about $3-4 ea and a quality bi metal hole saw like lenox could easily run you about $15-20.