Check with us when you're ready because while they may not always be on the website (but they are currently listed) we're always trying to build up inventory of the 4x4x2 boxes when we can so we can sell our Extreme kits.
https://www.wildhorses4x4.com/product/Extreme_Duty_Steering_System/bronco_Power_Steering_Kits
We have sold the boxes separately in the past, so may still do. Check in by phone and ask one of the guys on duty at the time.
Our swap meet (Bronktoberfest kind of thing) is not until later in the year. But our Roundup is a go as far as I know, and will likely be the middle-ish of May.
It's not etched in stone until you see it on the website, but as they say in hot-pepper eating contests and drone targeting circles, confidence is high.%)
Good luck.
Paul