Ive used a walktroughwalls code, since i couldn't find the above mentioned ledge.
Sad thing is, you have no pokeballs&pokedex from oak, since the shop is buggy. So you have to do with the 1 pokeball you find in the forest......
**hugs recently captured gastly**
Some NPC's still name the forest "Viridian Forest" and when in front of your home town gym, it says:"Viridian Gym, closed"
EDIT:
- It seems that the shop after the forest is also glitchy, might as well use some codes for pokeballs then.....
- Ghost gym pokemon have the same Rock/Ground pokemon moveset as Brock's pokemon. Also, some dialogue says he is Brock instead of TJ.
- A boy who shows you the mountain has a lot of messed up dialogue.