So the car is now SORN for the winter, and yesterday I took the opportunity to strip out the interior to expose the inner floorpan

Check the google drive link for photos and a video https://drive.google.com/drive/folders/1bv_IyVF6GCa8Iy3VzYooOsIdeRZLHG4R


Anyway the floorpan has bumps in the middle due to being incorrectly jacked at some point, hence my desire to fix it cosmetically

So next steps will be to drill from underneath the car to get datum points and cut out the inner floor

Then from here I can then straighten the bent box sections and also prep the are for fitting the Alfa GTA subframe struts

The idea will be to drill holes in the outer floor box section that’s currently bent, weld in a couple of nuts to make them ‘captive’

Fit the subframe braces at the new mounting and also through the existing subframe fixing points

Check the security of the nuts I’ve welded in, then weld the letterbox of inner floorpan back into place

Then clean the welds up, apply some paint, and no one would ever know!

Then refit the interior, and it’s job done

Cheers Jamie

Looking good! The Alfa braces are in the to do list for mine too. Way down the list behind fixing a solid amount of rust mind. And likewise I've got the obligatory floor humps from various tyre shops.

My plan of attack is similar except I planned to fabricate a pair of plates with captive nuts on the bench. Cut the corresponding hole into the lower rail, edge set the surrounding panel and the weld in the new plate. I thought that'd give a good hard point to bolt to

I have bought the tool for doing captive nuts, but as the floor isn’t flat where it would need mounting, I thought it wouldn’t be a good fit

So I’ve bit the bullet and will do as described

The only thing I might do is weld additional piece of plate inside the box section, just to be sure the mounting point is 100% solid

Cheers Jamie

Apologies I wasn't clear I used captive to mean retained; I didn't mean the rivnut type of fasteners. I tried some of those on the rear for the exhaust hanger that had a snapped bolt and they pulled very quickly through the chassis. I think it definitely needs plating to hold. I have 3mm in mind. I think the question is if you want that plate semi floating or not. If you do, you could consider using a captive stud (welded bolt dropped through from the top). But which ever way it all needs to clamp up flat with good amounts of land around the fasteners that is also flat ( something like 4 x fastener diameter for example)

No problem Szkom, regarding the plate, I will weld it into the box section rather than being just a sandwich plate

Cheers Jamie