You'll have a seriously hard time steering and controlling your truck with 8" wide rims on it.
The original rims were 16" dia x 4.5" wide . I wouldn't use anything wider than 6" but 5" would be preferable.
Ol' Roy had 15" x8" rims on it when I got it and they sucked! You could hardly steer the thing, even at speed. The ride was jarring and unstable.
16" rims and tall tires made a night and day difference.
