tinbarn,
Since this is your 1st post, Welcome to the Stovebolt!
Unfortunately, Ed's reply above is the definitive "short" answer on your question.
Depending on what you are trying to accomplish (sounds like you just want a better starting off 1st gear) you may want to consider changing the transmission to another unit that will achieve that result.
There are many options, from using a period specific 3 speed, a 3 speed with overdrive, a conversion to a T-5 overdrive 5 speed and others.
All depends on what truck, existing drive train and desired end result you are seeking.
Feel free to ask more questions, including ID of your Chevy/GMC truck you are working on, and folks will certainly jump in and try to provide more help as they can.
Dan
