Which bellhousing would be best

I recently picked up a A-body 4 speed C89126-8 and a A-body C13386-2 od 4 speed transmission to put into a 1969 valiant with a 340 small block (the car was originally a slant 6 auto).
My question is they came with 2 different bellhousings the first being a cast iron 2465523 (which looks to fit a 64 - 66 a-body) the second being a 3743859 aluminum for the OD transmission. Which bellhousing do you this would be best for me to use (I plan on using the C89126 and not the overdrive transmission)? Or is there a different bellhousing that I would need to get?