I didn't have any issues with my stock 20" radiator but I'm looking at installing A/C and I'll need the larger capacity radiator to support that upgrade.
This kit is "out of stock" a lot and you have to catch it when you can.
When I ordered mine it shipped without the radiator and I had to contact them have it shipped seperately (added another week to the complete kit delivery). There's a video that Don does showing the installation and it is pretty much as he shows it. The only issue I had is when the new fan is reinstalled on the pully, Don makes a comment about "hopefully the pully is still indexed" (or something to that effect) and I didn't quite understand what he was meaning. It turns out what he meant was the bolt holes in the water pump shaft align with the pully holes. Of course mine were not and it took me a few minutes to figure out why I couldn't get the clutch bolts into the water pump holes. But besides that it wasn't that difficult. One other comment I have is, be careful with the actual radiator, I have several scratches in my top cover paint. It was caused by just laying a tool or 2 on the top. It scratches very easily.
The kit comes with all the parts, but I seemed to have an extra set of lock washers (bag number 4088), never used them, maybe spares?