I also posted McMaster-Carr PN's for shims. I only used the 0.1 mm thick ones, which increases pop pressure ~100 psi. I think +/-50 psi is sufficient, since hard to measure much closer and it will change over time anyway.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans