A reader, whose name shall remain hidden to protect his identity :-), shared this cleaning technique with me;  Try the dishwasher.  Technically, the cleaning was already done, but the dishwasher added a nice finishing touch.

Here’s his description:

“With my frame changes completed, it was time to mount the engine.  The first thing I had to do was clean it and add some paint.  This engine has lots of cast aluminum mounts on the front. Unfortunately, the parts had a lot of surface crud. To clean them I used muriatic acid and elbow grease along with Mothers Aluminum cleaner.

Next, I put the cleaned parts into the dishwasher.  WARNING:  only do this when your home alone!

Finally, a little air drying resulted in some good looking parts.  Below you can see the below and after images of the engine.

One issue I ran into was that my oil pan hung down too low.  I thought a marine pan might be shorter, so I looked for a marine application and found one on Ebay for $15.00.  Though I had to change the sump tube on the oil pump, it turned out to work perfectly.

Now, the new oil pan is almost as high as the bell housing. Note the transmission (which I purchased from Dave).  I have the Sm420 with the 18 transfer case AA adapter. I used their two blocks and mount with the stock cross member. I had to add a 3/4 block under the mount and used two more blocks to drop the cross member. The output shaft is in the stock location from left to right.