First, the "Rocket" series engines were built by Oldsmobile.
GM used Borg-Warner, Saginaw, and Muncie transmissions in their manual cars. If you have a BOP bell housing to bolt to the block there will be numerous transmission options available. Most of the original transmissions were 4 speed at most. There are later T-10s, Tremecs, and McLeod 5-speed transmissions which could be adapted.
Pontiac used a valley pan and open web intake on their V-8s. Aftermarket intake options are limited. About the closest off-the-shelf intake to a tubular you will find is either a Victor or Torker II, but neither of those are optimal for a street driven truck.