May I humbly suggest to anyone who is chomping at the bit to get started...take the time to do some review on your site.
Is there anything that you'd like to do to make your pages more consistent?
Like adding breadcrumbs, or...
Putting all your adsense code in reusable blocks, or...
Other other types of reusable block uses/placement, or...
Adding breadcrumbs, or...
Can you do more internal linking between pages since you last published a page, or...
Whatever suits your needs.
First make yourself a spreadsheet of all your pages. Even C2. You'll need something to keep score on.
While you don't need to put them all in order of traffic, put your top traffic pages in the first slots. (If I take the first 50 pages, I've covered 50% of my traffic-my site has about 1400ish pages.) Given that (per my GA) readers view my site on Chrome 34.4% over the last year, by doing just this first batch, I've got the majority of my traffic covered as 'Secure'.
If your top income producing pages deviate from your top traffic pages you should consider swapping them in instead. That is your decision. Mine are fairly consistent between traffic and income.
Take inventory of your pages as you go along on the things you've decided are important. Give yourself other columns to note the status of your work. You may want to note what affiliate links are on the page, possible new pages to write to support this one. Do you have social media images made. Where are they. Should/can a light C2 page be honestly bulked up or merged with another(s). Should it be deleted? Etc.
The spreadsheet can get pretty unwieldy pretty fast, but remember, you can hide columns when you're working on specific aspects of your site.
I admit, this IS
a pain to do.
I did it earlier this summer while changing around the formatting of my tutorial pages to make them more uniform (225ish pages), changing the formatting on directory pages (110ish pages) and adding breadcrumbs to every, single, darned page.
My goal was 10 pages/day. The job was finished in just over 2 months. Regular site work could happen AFTER the 10 were done. I'm a 'list-checker' so an unfinished list is like someone throwing down the proverbial gauntlet.
But as long as you're taking the time to open pages (which takes a certain amount of time) it's a good time to take inventory.
And let's face it, a well-run, profitable business has a good handle on its inventory. And our pages are our inventory.
I hope this provides some ideas for tackling the transfer to https and makes the inevitable work more palatable.