I'm currently running Runelords for my 5e group, and the conversion does take a bit of work. For as quick and dirty as you can:
1. Throw out the money and magic items in the book. Random roll from the DMG, if you have it, every time the story would suggest there'd be some treasure (NOTE: "Story" means the actual thematic story, not when they suggest treasure should be found). You'll still find that the party will have a lot of money, so don't be afraid to add in stuff for them to spend it on, a la business investments, etc.
I also, since the world of Pathfinder is fairly magic-item heavy, allow the players to purchase select magic items at various shops around the big cities--once they leave Magnimar at the end of Chapter 2, though, the magic item options at the shops will be slim pickings, other than HP potions. I just roll on the DMG's random magic items from the Treasure section to determine shop inventory, using the average party level to determine what Challenge rating to use for the tables (pg 137 in the DMG).
2. Reduce skill check DCs by 5. That gets you into the ballpark, usually, up until level 10ish. After that, reduce it by 10.
3. Ignore XP for leveling. I find it better if you use milestones. If I had to do it over again, though, I'd probably put a bit more work into making XP leveling function, rather than use Milestones, since the "2nd Edition Feel" is something that the party enjoys, and didn't like about 4e at all.
4. Use the DMG to modify monsters as needed; I haven't tried the converter mentioned above yet (but I definitely will be, once the party have caught up with what I've already finished).
EDIT: Another reason I decided to use Milestones was so I could allow the party to get all the way to level 20 just before they enter the final dungeon or thereabouts, because we've never reached max level in a game before.