I was looking for that, too. I've been very disappointed with MediaFire now having all kinds of Pop-Ups and all the links on my Blogger point to them. I wanted to stop using them altogether.
After many searches, I didn't find anyway to post on Blogger...only "How to imbed PDFs".
WordPress, however, allows posting of PDFs and I'm now in the process of switching over to them.
I like that because it gives you more control of your downloads.
Maybe you should look into that.
Here's what I do.... I have a group on NPT called direct link, if you make a discusion and add some PDF's to the discusion it creates a webpage with the PDF on it.... then ou can just use your blogspot post and link to that page.