Ray Whiting

Hi I am restoring a 1929 Plymouth Model U Coupe. There was no carburettor or manifold with the engine so I am looking for both parts. However I was told by one source ( and this is confirmed on on internet site ) that the carb I require is a tillotson FR-1. A reputable carb restorer/supplier in the states says the original cars had a Carter RT-08 but recommends fitting a Carter BB1 as fitted to Later models. Can anyone confirm what is the correct original fitting.