Not sure I like the front half that covers the floor beams.  It LOOKS cool, but you already have a separate floor beam with flanges welded to the floor.  Then add another cover over that with more welds on the bottom of the floor?

I did mine differently. I used the (way cheaper) Tin Man connectors and a pair of new floor beams, with extensions for the tinman connectors that extend as far forward as possible to where the frame kicks upward.  Removing the old floor beams allowed the entire new extended assemblies to weld to the car all the way to the front kickup.  Then weld the new floor beams under it and the extensions are then hidden.   Check out the underside pics of my car shown in next post where it shows the finished product. 

Only downside I see on the spintech beams are they are only using a hat section rather than a rectangular tube   The floor of the car forms the top half of the new “beam”.   Probably strong enough for street use.  I just prefer one beam all the way from the rear kickup to the front kickup.  More work to install, but overall neater in my opinion.

That looks wonderful but there's no way I could achieve that level of quality if I did it myself.
That would be the project that ultimately took the car off the road permanently unless someone else completed the job.
I replaced the floors myself 20 years ago and I put them back into the stock location so I assume that these will work but may require a bit of trimming or massaging.
Capping the frame stubs with this system seems like something I could do though.
Thanks for the input.