Roy, based on your pics I've definately got a TH350! The angle on the back right corner of the plate is a giveaway. Also mine does not look like the pic of a Powerglide tranny. So, I've probably got to take it to a tranny shop and get them to look into why my Turbo 350 3-speed isn't shifting from 2nd to 3rd gear. Hope it's a simple fix.
Thanks for your help!!