Start at last post on the the bottom of this page and keep going thru pages 3 and 4. The trick of adding washers then another quarter turn on the bar worked for me, the trick was patience.
Finally removed the front engine bolt after days of gradual persuading with Halfods 24" bar.
However the rear one is well and truely F£%$"ed left hand thread damaged where the motorworks stand has fretted against the thread and the right hand side has snapped flush with the frame lug.
I've now cut through the spacer section and left both sides to soak over night again.
I thought working on an airhead would take my mind to a quieter place
Dammit, that stud is really stuck isn't it ? So, have you now got access to both sides of the frame innards ( ie the spacer is removed etc ). I can only suggest heat and a big hammer at this stage...with the frame suppored on the inside..plus lots of plusgas overnight soaking....failing that...the drill will have to be brought into action with an accurate centrepunch hole and the the hole drilled larger each time until it decides to pop out !!
Yes I cut the spacer out with a hacksaw blade last night and its now completely removed.
I've also supported the front of the engine and removed the front mount bolt and carefully raised and lowered the engine to break the seizure partially and this worked great.
The near side is relatively free at the engine lug and seized solid in the frame lug and the off-side is relatively free in the frame but seized in the engine lug.
I've been applying heat to both seized locations and copious amounts of WD40.
I'm contemplating welding a nut to the damaged thread on the left side and using the nut to try and turn the bolt until loose.
Still thinking about the right side as there not a lot to work on.
If all else fails I may have to cut through the bolts either side of the sump and remove the engine then deal with the seized bits.
The engine bolt is suprisingly easy to cut with a new hacksaw blade.