The axle and steering was changed. With a bit of thought and fabrication you should be able to make it work for you.
the front axle on the later models have a steering rack on the folded steel axle and the earlier model had a steering box on the frame with drag link to operate the track rods.
From what i can see, the kit comes complete with a new steering rack, so all you should need is the later type steering column retrofitted to the frame. You have a three bolt type with a steering box. You will need the four bolt type. should be able to find a used one fairly easily, then you may have to make an adaptor plate to bolt it to the frame as your current one bolts directly to the steering box and has a different drive to the later type. You may be able to adapt it to work with the kit supplied steering extension therefore not needing a later style column.
I am sure someone will be along shortly to verify if i am correct or pick up on something i have missed. Also, if you have a brekers yard for carts locally you may find a rusted out frame to cut the plate from and weld it into your your frame. that part rarely gets rusty.
You can clearly see the difference between your frame and the later type in the video below at approximately 9 minutes in. Yours will not have the plate that the column bolts to and this is what you will need to change along with the later column, or adapted three bolt column. everything else should be the same. The springs on the later type were shorter than the earlier ones, but that make no difference as you will be discarding those anyway.
https://www.youtube.com/watch?v=yap-13GMrb4
The only other thing to consider is the rear lift may be specific for electric or gas. make sure it is correct for your cart, although there are ways around this too.
If you have a cart scrap yard or dealer near you you may find a rusted out frame that you can take that plate from to weld into yours making the job even simpler.
I am sure someone will be along shortly to correct me if i am missing something. Its been a while since i worked on EZGO's