I don't know the answer to your question, but if Rick's can't help you, try a different vendor. I usually deal with the Truck and Car Shop in Anaheim, CA. They have great customer service and might be willing to measure both for you. Of you can try Steve's Camaros. Steve's a great guy and always tries to help. Finally, if neither of these can help, try Classic Muscle.
I wouldn't even bother to ask Classic Industries or Heartbeat City.
Tell them you don't want the overall length. You're looking for the HEIGHT of the line going from the fuel pump to the filter. The overall length might be similar, but because of the bends, the HEIGHT may be different. Also have them check the height of the line going from the filter to the carb. Not the length, but the height.
Ed