I too remember Merv during his tenure as a Reds' pinch hitter and reserve outfielder. Think he also played a little first base to give Perez the occasional day off. And yes, he was with the Big Red Machine in 74 and 75, including winning the World Series.
Do you remember Ted Ulander? Another Reds' reserve a year or two before Merv signed with Cincinnati. Cincy was Ted's last stop in the majors, and clearly his better years were behind him. I think he hit less than .200 with Reds. I knew a guy in high school who could not figure out why the Reds didn't trade Ted for Rod Carew.
The name didn't ring any bells (Ulander did, but could be anything)...
Baseball Reference had a very intriguing reference:
December 10, 1969: Traded by the Minnesota Twins with
Dean Chance, Bob Miller and
Graig Nettles to the Cleveland Indians for
Luis Tiant and Stan Williams.