Back then there wasn't much "store bought" racing equipment so you just used what you had or could find. Mostly you'll take stuff off instead of having to add a bunch of stuff. A 3/4 ton truck hub for at least the right front and some marginally wider tires and you're off to the races.
Here's a link to the modified and sportsman part of the only site a race car builder will ever need.
http://www.randyayersmodeling.com/modelingforum/viewforum.php?f=17&sid=44c134672bca5886c5a10415619909dc
There's some really helpful good guys on the "Darkside" section there too.