Progress; in a way...

July, 2016
Although I have been poised within less than an hour from this point for several weeks, the frame is completely off the engine now.  Tracing and evaluating the wiring and electrical components, as well as several other minor steps and other research/restoration considerations occupied much time these past few weeks.

One new revelation is the state of the universal joint; at first brief inspection, it seemed intact and in good shape except for a distinct lack of grease and the 'dry' state I found it in.  Upon closer inspection, one bearing was found to have a broken cap (vertical split is just visible below), exposing the top of a few needle bearings; that joint motion is essentially locked up - to the point that I don't know how it turned at all.  Little to do but replace the joint with new; although I will likely send this one out for rebuild for the next time.

This also means new bearings (carrier and sw/arm).  This is about $250 I had not planned on spending.

Some other unexpected elements adding to the fun.  So, the bushings on all four shock mounting lugs were very tight, and made removing the shocks more difficult than should be.  Three of them required a fair bit of effort and prying to remove (thankfully the frame was yet to go for sandblasing/paint).  The fourth, left side bottom on the sw/arm, would not come off at all, in a large part due to the nut stripped near the end of the bolt threads.  I ended up taking it off as a unit with the sw/arm.

After checking that I could purchase another lug easily enough, I used an air cutoff wheel to cut a slot into the inside end of the bolt to get a large slotted screwdriver on it.  Would not budge by hand or with impact driver.  Penetrating oil did not loosen it.
Next try.  The space between the shock bushing and the sw/arm was too tight for a 17mm wrench; but some more prying and bodging of the rubber bushing opened a little space and then pounding the wrench in with a hammer worked.  But it still wouldn't turn the lug bolt.
Next I pushed the bushing back towards the sw/arm to free up space at the nut end.  The cutoff tool again was employed to cut off the end of the bolt (after photo below).  This was successful, and much prying later the shock was finally pried off the bushing.  The bushing is essentially fused (rusted) to the lug.  But at this point, the threads in the sw/arm were loose and easy to unthread, finally removing the lug with bushing attached, from the sw/arm.

Apparently new shock bushings and/or new shocks, plus the mounting lug must also be added to my list of unplanned items to purchase....!
But, everything is finally ready to go for sandblasting and paint!