In adding or converting these sets to AUTO START I found it easier to remove the top cover/s and give myself some room to work, best I recall all the screws are 10/32 hex head no slot, seems like 2 lengths for the large part, mark your spots where you have a keeper nut, save yourself the effort of trying to fit a nut onto the bolt. The corners and lap joints will typically take the longer bolts because your going thru 3 pieces of panels/covers. There is a logic they use where washers are used and not used, then it gets worse, sometimes the washer will stick to the cover or bolt, you can generally see the paint pattern, use some drift pins or taper punches to help keep everything aligned and set the torque a few places to keep the alignment, then go around and tighten all of them, if you do this again and you just want to be anal about exactly where what comes from get you a piece of cardboard and nail or ice pick and when you remove a bolt put it in a matching location on your cardboard template then it pretty near is screw up proof..
good luck, others will have more improved methods, whatever works best for you is the solution you want.. mac/mc