We don't have basements in NZ... weird, I know.

But would a towtruck do the job? Just back up over the entrace and drop the tow cable directly downwards.
Attach it to the boiler, then winch it out.

As a scrapper, or a mover of heavy machinery, it'd pay to get to know a good tow truck firm and driver, get their card, keep it handy.
After years of shifting machinery, then one day getting a forklift (that I 'borrowed') bogged down in gravel while shifting a lathe into a shipping container, with a wasps nest somewhere nearby....
My mate suggests " A tow truck......?"

Absolute watershed moment....