going to get one of my 3310's ready this fall to play with. gonna stay with the sec. plate cause i have about a half dozen of them in my hand. all these plates have 34r9716b on them with a 21 stamped on them. what are the odds that after about 20 years of messing with these they are all the same. is there a better way to find the idle and main holes other than using my numbered drill set? ran a 3310 back in the 90's and had very good luck with it. thought i read somewhere that they had more numbers on these plates that would show the specs. would like to jet a couple up a tad just to play with and see what happens. running an edle. q-jet now and it performs great but would like to compare it to my holleys. going on a 350ci 375hp sbc with hyd. roller and vortec heads.