Something you need to understand... if there is an easy way and a hard/complicated way to do something... I will take the most hard and complicated path... not because I like doing that, but because I lack the wit to know, or identify, the easy way... I should have asked my father-in-law. He is quick to come up with easy solutions like the one you suggested.... son of a gun...
Not a kit already available... I just put a kit together to do this...
This is what I got:
2 Pack (yeah, now I will have a spare shaft for any other projects! )
AR-PRO (2-Pack) 5/8” x 36” Zinc Plated Steel Rods Designed for Use as an Axle Shaft on Hand Trucks Dollies Wagons
4 Pack
AR-PRO 4.10/3.50-4" All Purpose Utility Air Tires and yellow Wheel - with 10" Inner Tube, 5/8" Axle Bore Hole
3 sets of 5/8"
set screw shaft collars
2 sets of 5/8"
Pillow block bearings
There are several house around here, being built. So I just go over to the trash bin and pull out discarded 2x6... that will be used for the frame.
Oh, and to make the swivel front steering, I got these to insert into the two pieces of wood, with a piece of shaft and two collars...
5/8" bore bronze flange
Now I am thinking if a bolt would have been fine for this task... goodness... I need help.
I am trying to make something like this:
View attachment 465276
And was using 2x6 instead of 2x4 because the pillow blocks were too wide for a 2x4.