[Tom Goldman]

MSD rpm chips or pills are just resistors inside the casing .
Resistors come in varying degrees of accuracy or tolerance . the most common ones are 20% . with better more precise ones being 10 or 5 %.
Your difference in RPM less than 2%,which is really very good , I've sorted thru as many as 5 or 6 pills sometimes to get an exact rpm.
I'd try a 6300 chip to bring it closer to your desired 6200.
Other things that affect rpm accuracy are oxidized pins on the pill and loose sockets on the 2 step module .
Hi temperatures can cause resistance to change also . .. Something to consider when locating anything electronic.