while I haven't set it up yet, I have a original Fenton intake for my 216 which uses the smaller 216 carb. With your 235, your only choice of Carb is Rochester. For my 216, I have a pair of Strombergs (2 bolt not 3) but I also could use a Rochester, Carter or Zenith carb on my 216.
When going with dual carbs are they far enough apart to use stock air cleaners, this would be on a '53 pickup. The intake for 216 and 235 different carb bolt pattern? I have a Zenith on it now and have another set back waiting. What about carb linkages, do either of the intakes allow the stock lingage?
Measure the spacing of the carb studs. center to center. The 216 will be 2 11/16". The 235 will be 2 15/16". The 216 has a smaller bore and smaller ports. Also the heat connection is different even though it looks the same. If you have a Zenith, I believe it's for a 216.