Using multiple windings on two transformers to create one output at maximum power

Hi everyone, I've just resurrected a broken Weller TCP1 and need a 24v ac supply for it.

I have a 23.5-0-23.5v toroid that I was just going to use half the winding - but it's overkill (8A rating) and going to be very big and heavy.

I've also got a pair of identical transformers with 8-0-8 and a 16-0-16 secondary windings.

I'm thinking of paralleling a 16v winding on each transformer, doing the same with an 8v winding and putting the two in series to give the 24v. However, that leaves two 16v windings and two 8v windings left unused.

Is there any advantage in paralleling those windings also? Any disadvantage? Or just leave them unconnected...Which is what I was about to do..

Sadly I cannot split either winding into two independent ones.