I don't believe air conditioning had any impact on the exhaust manifold for the base 327 engine. Only other part numbers that I know that were used on 327/210 hp Camaro in 1969 are:

LH 3942527 and RH 3946826.

The "527" and "826" manifolds are shown as correct for all manual transmission, with A.I.R., small block Camaro applications for 1969 including the 302 Z28 engine. These manifolds have A.I.R. drilled and tapped connections. If A.I.R was not used, the ports were plugged. (See JohnZ's comment below.)

From personal experience, I removed a set of the "527" and "826" manifolds from a 69 327 base coupe that had a 3 speed manual and no A.I.R. The manifolds were required because of the 3 speed manual trannsmission. A.I.R had been removed so the ports were plugged. (See KurtS and JohnZ's comments below.) This "527" manifold is currently on my car.

In 1969 Camaro SB applications, there is a distinct difference in the RH manifolds between a standard transmission ("826" manifold) and an auto transmission ("376" manifold). The "376" manifold incorporates a heat stove, is wider, with the heat stove riveted to it. (The "826" manifold for standard transmission cars does not have the heat stove, since the Thermac / heat stove was an emmission system only applicable to an auto tran setup.)

I believe the manifolds you need are the "529" and the "376" manifolds.

Attached pic shows the "527" manifold on my engine. Since the only fundamental difference between it and the correct "529" manifold is the A.I.R. ports, I decided to go ahead and use it. The A.I.R. ports and hex plugs are clearly visible.

I will also post a pic of the RH side of my engine with the "376" manifold and heat stove.