OK I have an 89 D250 and I'm trying to fix the wipers, and I think the fuse may have blown. I looked all over this thing, and I don't see a box or panel anywhere on it. Stupid question for sure, but I don't have the book for it or anything and this is old school tech so I need input. Flame away! Thanks!!

 

There is a panel under the steering column held in with 4 screws. It is behind there.

 

A lot of times the wiper motor will lose it's groung. Try grounding the w. motor to the firewall with a screwdriver and see if it runs. If it does just run a wire to a screw or bolt on the firewall.
That's all it was on my 87 D100 and 87 5th ave.

 

Found it. Thanks! I really need to get the book for this thing. Anyhow, here's the story of what was wrong.
I installed the fuse, and I could hear the motor turn, but still no movement from the wipers.
Next step, remove the cowl to find the arms are just laying in there, disassembled.
The reason? Those little plastic grommet type deals were all rotted out and gone.
So I go to the dealer and get the very last ones they have (whew!) and begin to reassemble the mechanics of the wipers.
God help you if you have to do this with hands bigger than a vietnamese woman!
After a lot of sweat, a little blood, and a few things I will surely pay for later on, the job is done and I have wipers!!
I will never take them for granted again.

 

Did mine a while back but I took all the linkage out through the holes in the cowl area and assembled it on the work bench.
Auto Zone and O'rielly's have in the help section if ant body needs them.

 

i had to do this also.i have heard to use some grease it will help go on.i used a rubber hammer to help put them on

 

Hey thanks for the tip about the Help! section at the parts store. I never realized how many of those parts actually fit the old truck! Also, they had the tail light lenses right on the shelf! Great find!