tall decks are suppose to be a little stronger block......should defintley have a steel crank and pink rods....yes you can run a regular manifold with spacers.......i was told the tall decks allow for bigger strocker cranks also but not sure.....those are pretty rare dudes id buy it if the price is right........p.s. gm also made a 366 tall deck that alot of those trucks had in them and they arent worth a shit.....make sure its not a 366!!!