The units of measurement interestingly cross at a #70 drill bit. A 70 bit is a 70 jet. A 68 bit is like a 72-74 jet.
Like Kevin says, don’t drill it till you know. Depends a lot on your elevation and temp as well. If you’re over 1.5 turns out on high with cold ambient temps, then drill it.
I drilled my 1128 competitor for the 2018 MMWS buildoff to a 72 jet. At 60* and 230’ ASL here, I was 1 turn out on high with the saw hot tuned to 14200. I get to Randy’s and it’s 89*, 100% humidity and 2300’ ASL. I had the H screw bottomed out and couldn’t get the saw above 12000 rpm. Had to buy a HD14 off Dave to run. Part of why I did so bad in the 1122 buildoff, couldn’t get the saw I built for rpm to get over 13000.
A lot of guys run the .58 jet HD50 on 044/446/046 and say it improves performance.