88stang5.0GT

i got my 1988 GT back from the body shop that refused to do any work on it because i didnt want them to fix everything....
but now i get to upgrade and make the 5.0 even more amazing than it is.... the first step is to send the block to a machine shop to make it a 306
i wont have my license for at least 6 months so if anyone has any ideas for my car like any specific parts that are better than others let me know because im basically replacing everything