Core plugs - material and installation

[Vertigo]

The Silvertop in my AW11 developed a hole through one of the head core plugs (underneath cylinder #3 throttle body). Ive popped it out, but had such a bitch of a time trying to get the new one in, that i bent it out of shape. Have a new one now, but damn, space is super tight, angles are difficult.... any suggestions? Thinking either take the throttles off, or the cylinder head itself.

Also, what material should I be using? Steel, or brass? The previous one was steel, very magnetic.

[Dell'Orto]

Remove a driveshaft and see if you can access it easier from underneath? Brass is better, doesn't corrode.

[MAGN1T]

Use antifreze, then it won't rust out.

[Vertigo]

Quite, but this engine came from any number of cars previously, and I came with the car when I bought it last year.

Anyway, its replaced now. Gave up and had a workshop do it!