the use of impact will help loosen a bolt that doesn't want to budge. Obviously you can snap a 13mm bolt with a 3/8 ths drive. But you risk breaking the bolt using impact. Can you heat the bolt? What about access to any exposed threads? If the bolt passes through its connecting member the threads on the back side can be cleaned and lubed proir to removal. Alternately, gently feeling for the bolt loosening then re-torquing, following that sequence to loosen. Otherwise, snap it, grind it drill it and heli-coil it. Easy-outs work for bolts that are "easy to get out" and that is all.

Just my 2 drachmas worth.

good luck and may the winds of patience blow in your favor...

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92 300e old but clean
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