I investigated this a long time ago (25+ years ago).
As far as the column goes, there are six (6) basic groups of columns used in all FMJ vehicles:
- ’76-79 FM tilt columns (note: other than a few minor odds/ends and wheels, there is not much that interchanges with the other 5 groups).
- ’76-79 FM non-tilt columns (note: other than a few minor odds/ends and wheels, there is not much that interchanges with the other 5 groups).
- ’80-89 FM tilt columns
- ’80-89 FM non-tilt columns
- ’80-83 J tilt columns.
- ’80-83 J non-tilt columns.
These last 4 groups – there is a lot of interchangeable parts between them.
Of the 6 groupings, there are column shift, floor shift automatics and floor shifted manuals (all three are slightly different). I’ve been told they made column shifted manual columns (three speed on the tree) – but I have yet to see one (yet).
Chrysler changed electrical plug-ins and other electrical parts every couple of years – so there is not much electrical interchangeability between all 6 groupings. If you have an electrical part that has a different pigtail on it, in most cases, the pigtail connector can be interchanged and/or electrical pigtail can be cut off and soldered back on.
The floor mount (at firewall) is the same for all FMJ’s (and only to FMJ’s).
The overall length is the same on all FMJ’s.
The dash mount is different on J’s vs. F & M’s. If you look closely, the dash mount is a few inches more forward (closer to the firewall) on the J’s, because of the dash design difference.
I’m sure a person can alter the dash mount bracket to fit a J into an FM or vice versa) – but you would need both columns and several measurements to make sure its welded back in correct place.
Also, I recommend dissembling the entire column before welding, just to make sure you don’t damage the bearings or other electrical components (if welding is to take place).
The upper portion of '80-89 columns is the same for pretty much all Chrysler cars/trucks (except for Omni/Horizon (L body) and vans) made in the ‘80’s, so a person can find floor shifted (manual or automatic) front wheel drive, pickup or Dakota column and can transfer/interchange (the upper) parts to convert a ’80-89 column, if wanted.
I’ve also heard the ‘80’s GM steering columns used many of the same parts (Chrysler used Saginaw (GM) for their ’80-90ish columns) – so that might also open up other possibilities. I’ve not looked close enough to know for sure.
The same applies to '76-79 non-tilt columns. The upper part interchanges with most of the '70-79 vehicles (to adapt into a floor shifted car).
I don't recall seeing many '70-79 floor shifted tilt columns - so if made, those column parts would be hard to find).
I hope this helps.
BudW