I don't know if I'd call the external oil line a 'shadetree' fix. It was pretty common. I posted this earlier, but looks like nobody read it:
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A bypass line can be added. Here are the instructions from a kit I found on eBay - http://personal.bellsouth.net/~fredrij/RockerOilerInstruct.jpg
Vintage Auto
http://www.vapinc.com/ carries these kits too (See Accessory Rocker Arm Oil Line Kit under Chevrolet - Rocker Arms & Shafts.) These will bypass the clogged passage that was a common problem on the 235.
I have an NOS kit and have one installed on my 235. Its a 3/16 copper tube. McMaster sells 3/16 tube
http://www.mcmaster.com - Home Depot and Lowes don't carry it.
This will fix the oil problem, just as well as restoring to factory...