One way is to find something to jam the part on the door so that it's outboard. One tool would be a cotter pin puller, a hooked shaped tool.
I don't remember what type of hardware holds the handle on. I have spend a considerable amount of my lifetime working with fastners as a way to put food on the table, so this is a flat-rate skill: There is a tecnique, whereby you hold the fastener in or on the tool. In a horizontal position--at the same instant--you let go of the fastener and quickly slam it in place, creating enough inertia to overcome gravity. This method can be done in a straight down direction too if you do it faster than gravity can make the fastner fall.
I also have #1, #2, and #3 phillips head screwholders--you know the + screws. They are spring loaded tips that are cocked, then inserted in the head, snapping into the screw. I also have 2 slotted head--the - screws--but slotted head screws always go in the trash can.
Magnetic holders such as magnetic screwdirvers and nut drivers help hold fastners in place for those pita positions.
You can also hold the fastener with needle nose pliers. You'de be surprized at how well one can manipulate fasteners with needle nose pliers. All you have to do is work out in the freezing cold with heavy gloves on. If you're a puss like me, with heavy gloves on, you'll learn how to install even the smallest jesus clips with needle nose pliers.
A pair of needle nose vice grips with just a tad of tension does an excellent job at holding fasteners. Make sure that you use just enough tension to hold the fastener; otherwise, when you release the grips, the fastener can go flying.
If it's a 5/16th or 3/8th bolt, you can wrap a peice of paper around the head of the bolt, and jam it in a nutdriver or socket. This holds the bolt firmly in the tool as you start it.
Screws can also be done by holding the screw on the driver, and passing a wrap or so of electrical or goose tape around the screw and the driver. You can also use a wad of dum-dum. The slang name for dum-dum is strip caulk, the soft silly-putty type of pukey. Windsheild butal--that nasty soft putty stuff that is used to install windsheilds.
With this list of holding fasteners, you should be able to find one of them that works for you.
