Alum Powerglide to a SBC 350

Hello: I am new to this forum, I have a powerglide in my Rat Rod and I tried to get it started, but the starter hung up in the flex plate. I thought it might of been the starter, but it wasn't. I have shimmed it and still nothing, so I thought the flex plate might be wrong or wrong teeth number. I have removed the motor and being very discusted I left it alone. Is it possible that I have the wrong flex plate or possibly in backwards. Sorry about this silly question, but I am no mechanic, I paint for a living....I work for the 32 Tide Team in Hickory NC....HELP PLEASE....I want to go to Pigeion Forge this fall.....Roger

There are only 2 flexplates for the older 350's. If I remember correctly the small one is 153 teeth & the large is 168 teeth. Either will work on your combination & can be purchased from a parts store for about $30.00. The starter for the small flexplate will mount with 2 bolts in a parallel line with the back of the block. The starter for the larger one will mount with 2 bolts that are stagered. You block is drilled for both starters. If you have a 400 small block, it is a different animal! There was also at least one year & I think it was middle to late 70's that some Chevy motors were actually drilled wrong & they went ahead & used them with special starters. Those are a nightmare!