Intake Manifold Serial Number - 3844459 Cast Iron 
RPO - L75 327 300BHP

Casting number 3799349 was for the early cars and changed to 3844459 for later cars.
The original bolts had headmarkings of M, TR, or AP. This is exactly the same as for the base manifold. These bolts may have been painted engine color, or they may be silver.