I have the flowmaster 70 series on my 68 K10. Dual 2.5 in and single 3 out. It's dang near perfect. It is a bit "Large", but my exhaust guy says tone not drone.

feedback from a real test drive to the local super market and back . . wow the truck is so nice to drive now and i am happy to drive it now . that flowmaster sucked on this truck & engine combo for sure .
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