Most light duty trucks sit just high enough that it's difficult to reach into the engine compartment for routine maintenance such as changing spark plugs or a distributor cap.  You can buy a top side creeper, but those are fairly expensive.  Some techs just climb in.  But, If you've ever ripped your pants on the hood latch or snagged a boot lace and had to do a stunt dive straight into the floor while climbing out from under the hood then you tend to prefer to stay at ground level.

Here's a simple idea that is often overlooked...

Let a little air out of the front tires.  You'll be surprised how much more you can reach when you do this.  Don't let all the air out!  You don't want the rim to damage the tire and you don't want the bead of the tire to unseat from the rim. 

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