In Ted's article, "A Tale of Two 330-Inch Y-Blocks," Isky Beehive valve springs were used on the ECZ-G heads. According to Isky, the bottom OD is 1.290; bottom ID is 0.885. The top OD is 1.055; top ID is 0.660. 

I plan to install Pac 1283 Beehive valve springs on my ECZ-G heads. The bottom OD is 1.250; bottom ID is 0.845. The top OD is 1.085; the top ID is 0.845. Should the cylinder head shop have any difficulty cutting the spring seats for the Pac springs?

I almost forgot to say Happy Thanksgiving!