What happens if both Trump and Pence are indicted?

Recent press reports indicate Pence may be facing his own legal jeopardy for giving false testimony about the Russia investigation. This raises a serious issue for me:

What happens if both Trump and Pence are removed from office at the same time? Who would the office fall to? In the line-of-succession I believe the Speaker of the House is next up, so would Paul Ryan become president?

What a cluster fuck. If it wasn't Ryan I'd say the House would never vote articles of impeachment, but because both Trump and Pence might be convicted, it seems like this might be a possibility after all. Yikes.

We need a "Lack of Confidence" vote like in the UK, where a new election can be called out of the blue.

I'm hoping for Trump, Pence, Ryan and McConnell to get marched away in cuffs, simultaneously. They all deserve it.

One off-beat scenario: Democrats get the House in the mid-terms, and then Trump and Pence are indicted.

President Pelosi, anyone?

Senate will never vote 2/3 for impeachment.

Not until after the 2020 elections anyway, by which time I expect the Rodeo Clown to be ancient history.