What g-rider said... a 235 or 216 will have the distributor in the middle, a 230/250/293 would have the distributor towards the front of the motor.
If you do have a 235, the bellhousings and flywheels will interchange allowing you to run the 6 volt starter and stock clutch.
If you found a 230, 250, 0r 292, you may still be able to use this engine, but you might have to swap out the bellhousing crossmember with that of a 54 or 55 1st series truck. You will also have to fabricate a new front mount, or use side mounts. Don't take my word as gospel, as I have never done this swap.