The finished article.
The design and dimensions were taken from Spectre #21 of 1976 (published by the Phantom III Technical Society). Many thanks to Ned Estridge and Bob Shaffner - it saved me a lot of time and trouble.
One pair of wheels is rigidly located whilst the second pair is on swivels.
My experience suggests two modifications :-
1) the height from the floor to the bottom of the lower horizontal rail should be reduced from 18" to 14" unless the user is well over 6 feet tall
2) in the UK planed timber is 3/8" narrower than the nominal dimensions given in the drawings - plus or minus the nonsensical metric conversion. Rather than build the stand to an external length of 36" it would be better to construct the stand with an INTERNAL LENGTH of 31.5". This would then allow the engine to be inverted with the timing cover in place and still rest the rear of the engine directly on the stand.
All other dimensions are spot-on and allow good engine location and clear access when working.