The new version of the SPA manifold has a center mounted wastegate but yes the old one had a side mounted wastegate.

This is the new one


this is what the old one looks like


I appreciate it but I've actually had good luck with the fel pro 1025 which has built in copper rings, the same compressed thickness, but a bigger bore.
https://www.summitracing.com/parts/fel-1025/overview/make/chevrolet


69 Buick Special Deluxe. Intercooled Turbo Chevy 250 @ 15psi on a stock long block. It's kinda fast.