Thinking out loud I had a " Extra job " at a demolition the boss used a " Tiger Saw "
to cut off nails ( Steel ) removing installed shelf's . With the right blade it can cut aluminum and so
I have one of those a bit large perhaps --- a work colleague or neighbor can have one
A bit smaller
Looking something like that below
The blade is going in and out back and forth
I believe Bronze is not so hard
Being careful with the machine and do the last part by hand and the Hacksaw blade
I feel it can be done OK it can take some time --like 4 minutes ( Only joking )
But so does taking it to the shop : And since you are experienced mechanic .
https://en.wikipedia.org/wiki/Reciprocating_saw
Yes I now se there is a picture of the same cutting nails
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