68 Block with 75 Head

[blaze65]

Looking for help with this 68/75 setup. Car has a autolite 1100 from an automatic car on it. Engine does start. Pony Carbs won't discuss a new carb until they say I get the Head corrected. I don't know who put this head on or what Pony thinks might be wrong but How do I check if this setup is built correctly and where can I get a good carb setup ? Thx