It would be great if your Dad could shed some light on how he had modified the engines and how much extra power they produced. The twin carb set-up must have quite sophisticated. Did he fit up special exhaust manifolds and a free flow exhaust system? It must have sounded wicked!
It appears that he took his Rallying seriously, was there more Rallies back then, then now?
How did he make out?
Sweet talk him, get him to share his experiences with you on tape for you and your family, FCCCi included.