A couple tips to make turbo'ing your BMW M50 M52 M54 less miserable (it is still miserable)
N54 exhaust studs BMW part 11127593376
Copper coated exhaust stud nuts BMW part 11721437202
M50 exhaust manifold gasket 11621728984
Turbo gasket affiliate links:
T4 https://amzn.to/3HsZtC1
T3 https://amzn.to/3HwTIDf