after market tach on rb26(i have a tach converter)

[drftnrps13]

ok just got my rb26 to run in my s14 this week and im sing an autoguage tachometer instead of my stock one. i bought the autometer tach adapter because it says u need it for any car running a distributor less ignition system. i followed there instructions which ill post below but no success! the tach at idle sits at 0 but when u rev it, u can tell it off!! im having a break-up in the motor when i rev it but cant tell the rpm? help anyone!

instructions i followed(the one for individual coils)-http://www.autometer.com/download_instruction/561.pdf

(and yes i set the tach to 6 cyl)