Season's greetings RATs!

I am designing a replacement power supply for a couple of Dyna Mk IVs.

Is it feasible to clean out the contents of the original can cap? Or will I
end up with a gooey toxic mess? I was thinking I could clean out the
contents of the original can cap and possibly insert 2 electrolytics. This
would leave me more room to work with under the chassis for the rest of the
power supply.

Tia,

-- Rev