Jerry, I suspect there's not an assembly manual for the Sherman because I looked around for you under Torro and they also only market 2 boxed kits - Tiger & Leo, both of which have assembly manuals.
Torro kits
And if you refer back to Taigen's site, they never show any box with their ARTR kits, only for the Tiger & Leo.
The ARTR "kit" you bought is probably assembled by IMEX from parts (nothing wrong with that). If you choose to move ahead with the build, I am sure Rich and Crius would be of great help.