Thank You to all that replied and offered suggestions and thoughts. I really appreciate all of the ideas, and they helped me get focused.
The engine is a Revmaster 2100-D-75. The prop is a Warp Drive 3-blade, non-tapered, 52". I performed fuel flow tests this morning and arrived at 21.8 GPH free-flow rate. In checking total travel of the mixture lever, I discovered that it was rotating only (roughly) 60 degrees, not the 90-95 degrees per Revmaster's requirements. Given this discovery, further checks were halted. I'm now in the process of locating or fabricating a lever with 3 holes, total length about 3.5" which can be used to translate 1.5" of cable travel into 2.5". Thanks to all for their help! Dave.
