parasitic drain problem

[Simca]

Hey guys i have a 1990 240sx hatchback with a rb20det .

when i check the battery with a meter it reads around 11.90 to 12.60 volts
. When i run the engine its only reading 11.60 and slowly drains on an idle.
When i drive around the block it drains extremely fast and dies before i getr around and i have to jump it to let it charge a bit to make it home.

I thought it was a bad alternator so i swapped it with another, exact same alternator ran the number with napa. once i ran the the new alti all my electronics died i checked the fuses and found that my fl75w/alt fuse and fixed it all my electronics are working now. but i still have the parasitic issue, maybe you guys have a clue wtf is wrong with it, please leave your comments and suggestions .


thanks in advance