T.M. - The give away on what the engine is or isn't boils down to finding and posting the block casting number and date codes, plus the stamped serial number on the machined pad just to the rear of where the distributor goes into the block.
Once you have that information you (and the collective if help is needed) can decode the info to determine what the engine is. Here is a great informative web page from our own "tclederman" -
Engine Casting Codes & Serial Numbers that you can use as a guide to finding the info on the engine. This particular page is showing a low pressure '51 235, but your potential "low pressure 235" would have the info in the same spots.
Gather the info and post and we can continue the how-to decode sharing into the next level - figuring out just what it is.

BTW - Posting pictures is best so we can also see what you can.

If it turns out to not be a low pressure 235 (perhaps a later full pressure engine???) this info can still help you locate what's needed to gather the data. Looking forward to seeing more on this.