Tnims68, What you are missing (probably) are the fillers that Ames calls "seal kit" FP454 for cars w/o a/c, or FP455K for A/C cars...in my older Ames catalog F-8C ,pg 103. they are/were $14 for a set..."these are the masticated rubber seals that are located between the core support and the radiator. They are used in conjunction with filler panels FP191K and FP191L"
which are the "X" fillers.....

And if it wont re-start when hot , you probably have haedars , right? or you might need this anyway...its the #FN405 , "solenoid heat shield" $10.00 ,"originally designed foir the 67 HO and RA applications, this shield helps insulate your starter solenoid from exh. manifold heat. can be used on any Pontiac V8 to reduce hot start problems. This willn not work on FN402P ( which is the "high torque starter")

hope this helps you!
Bjorn