Having one cylinder .020" over will not make a dime's worth of difference- it's done everyday with absolutely no problems. This is of course assuming it has been bored correctly. You said you had 120 pounds of compression. You said it idles fine, a bad seal would cause no or poor idle. I'm still leaning towards a TORS problem-it could be difficult to find, downstream from where you say you have it jumpered. You do have it jumpered on the harness side, don't you?
Jerry
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