so i building a old schwinn world
its horizontal dropouts but short ones, and im planning on running a flip flop hub.

is it common practice to drill or dremel out the filled section of the dropout?

is there a easy way to go about it, any writeups?

also im concern about getting the right chainline with my set up

the wheel set is a flip flop hub whell set from a redline 925...
using the stock bottom bracket i'll be running bulletproof cranks, should i have any problems how will i be able to space things out if need it??

last thing the frame i'm building is a 58cm, the drop bars i have are from a 54 which makes me think theyre to small. not sure what bars i want to run in the future. but for time being what kinda measurements should i check to make sure the bars are a good fit for me??