RZFD

I've got a NX kit right now I'm running a 35 shot on the recommended 31/18 jets in my '99 Si. I've got a Walbro 255LPH sitting in my room pending install once I figure out the jetting I'm going to run for a 75 shot. I'm running stock internals, stock timing, NGK 7's gapped @ 28, and 93 octane. Normally I don't like to stray too far from manufacturer's settings but I've been doing a lot of poking around and it seems many prefer to run totally different jetting. I planned on retarding timing 1 or 2 degrees. I can't do it too much because I don't have an MSD or Hondata that will do it for me so I need the timing to be daily driveable off the bottle. I also plan on going to an even colder plug probably 8's gapped the same. I've talked to a lot of muscle car guy and they say that the NX jetting do run a little lean. My basic question is how far should I stray from the fuel jetting just for a little extra margin of safety (NX jetting chart says 41/24)? Any other recomendations on my set up would be appreciated.

RZFD