I am currently using a pcm from a 2001 S10 that originally had a 4.3l. I have flashed the new configuration from a 2002 GMC Savana van and the tachometer obviously reads incorrect. After checking the setting, i have noticed that i am not going to be able to program this fix but am going to have to modify the IPC. MY question is that if I was to acquire a IPC from a 2001 or so Silverado that has a tachometer, and after changing the chip that controls the stepper motor for the tach, would i be ale to program the pcm to set the proper pulse no matter if the engine in the 2001 is an LS based engine? I am pretty sure that this should not cause a problem since only the reference signal is what matters. Any help would be great!! Thanks in advance