65 T code with 68 Block and 75 head

[blaze65]

Hi All, New to this forum and looking forward to the wealth of information from so many of the posts I have read. I am trying to get more info on my setup. I have a 68 block with a 75 head , C8/D5. I don't know who replaced this motor or what they did although with new points and condenser she started right up. I am hopeful to keep this motor for a while and would like to tune it as best I can. I was going to buy a new carb but Pony carbs was reluctant to send one until I get the head sorted out. Basically they said 'OH xxxx'. I have had others tell me this Block / Head combo is OK. I am sure they are right but how to I address the carb / log and whatever issues Pony carb was concerned about ? Where do I start with this engine ?? Many thanks