pulled the t stat out - it be flowing now!
the t-stat looks 'normal'. did a bit of web research and found remarks regarding 'balanced flow' t-stats...i have one for the 350 build we are doing..different looking critter. If the no-t-stat bit works i'll try the balanced flow one and see what results it gives.

since i have to road test it anyway, might as well cruise on over to Jerry's Curb Service, it being friday night and all...