Here is a diagram of the location of the 1954 truck starter button if so equipped.
You may also want to invest in the 1947-1955 First Series Truck Assembly Manual. It has a wealth of information about your truck right down to nuts and bolts. I have seen them on eBay...but I think folks like Jim Carter sell them too. The 49-54 passenger car guys would "flip-out" if there was such a manual for us.
![[Linked Image from c2.staticflickr.com]](https://c2.staticflickr.com/2/1698/26124566660_2f59b643eb_c.jpg)
And as
TERMITE DELIGHT specifies, you can operate a 6v starter on a 12v system. You just have to be careful to not lean on the starter for long periods of time.