The typical distributor position for installation in the 235 is with the grease cup about perpendicular or so to the motor (pointing to the left side). This allows the clips for the cap to be easily accessed and puts the stud for the coil wire at about the 6:30- 7:00 o'clock position. See the photo in the below link.
https://www.lowrider.com/rides/cars...evrolet-235-convertible-engine-side-viewFrom that point the wires are typically installed with No. 1 wire at the 4:30-5:00 o'clock position. You might consider installing the cap and putting a chalk mark or silver sharpie mark on the body of the distributor directly under the cap tower for the No. 1 plug wire.
take out all the spark plugs (if there are any installed) and bring the no. 1 cylinder up to TDC. Do this by putting your finger over the No. 1 spark plug hole and bringing the motor around until you feel compression. Once you feel compression, slowly (by hand if possible) rotate the motor and bring the BB on the flywheel/flexplate up to the pointer on the bellhousing or auto trans adaptor plate. Once done, the motor is at or pretty close to TDC (assuming a 57 flywheel or flexplate. Other years vary).
Now you can install the distributor. The trick here is that the tang on the distributor must engage in the slot in the oil pump (shine a flash light down the distributor hole and you will see the slot). If it does not engage, the distributor will not drive the oil pump. The reason this is important to mention is that it is entirely possible to install the distributor, get the motor running, and not have any oil pressure because the distributor shaft in not engaged in the oil pump. I have had this happen to me a couple of times so its important that when you first fire the motor up, if no oil pressure, shut it down and re do the distributor.
Getting the tang and oil pump lined up, while keeping the no. 1 plug wire at 5 o'clock or so might require a little fussing around so be patient. Use a screw driver to adjust the slot, install the rotor, move the distributor, you are likely to pull it out and reinstall a couple of times to get it just right. Once its in, center the hash mark on the octane selector plate with the hash mark on the distributor pad (can be hard to see sometimes but its there - coil side of the pad) and tighten the bolt down. Now install your rotor and move the distributor until the rotor is pointing to your chalk mark on the distributor body. Now tighten the screw on the clamp.
Your timing is at or just about at TDC and you can start the motor at that setting. Now install your cap, run your plug wires and install your plugs. From a timing perspective you are ready to go. After you get the motor broken in, you can recheck the timing with a timing light and adjust if necessary.
This is the way I do it for all my rebuilt 235 and 261 motors and they all fire right up although there are probably other ways to do it too.
