.... confirming that the 3 plugs are definitely for the short wiring harness for the 3 center console gauges. If desired, you can always add a used or new-repro console with either nice used/restored or new version (smaller diameter) VDO gauges, get a used or rebuilt/repro center console harness (Jeff Bowlsby website below - also look for & download his various electrical diagrams applicable to your 914 year/sub-model/engine), & just plug-&-play!
http://bowlsby.net/914/WiringHarnesses/IMHO for both floor & hell hole - you'll need to replace with either NOS-Porsche or Repro RD panels (or parts therefrom) - & get a lighted "snake camera" to look into the hole at the Longitudinals on both L & R sides to check for rust inside the Longs.
From what I see at your hell hole pic, there is surface rust at least, with a high probability of it going deeper - given that you're in a wet UK climate. So get a screwdriver & start prodding around everywhere on the Long, Suspension Console, Inner Fender/Side Wall area. I say do so even if the tray/support itself is sturdy, because it could be a newer replacement with rust issues on the other areas mentioned.
Also check the lower firewall both above & below the lip, & the L-side below the relay panel, & inside the tunnel while you're at it!
If not rusted - then you won't need to replace there, but the floor looks bad & may also have spots on the passenger side &/or behind/under the seats. The extent will determine which size/extent of repair panel to buy, since they come in L & R, F & R quarters & half panels, as well as the full floor.
If you have enough spots on there needing replacement, then you may be better off doing a larger panel cut & replace welded in at 4 straight seams - rather than trying to do a bunch of smaller patched areas - & it will be more sturdy if cut & replaced to the factory manual's recommended panel cuts/seams (you can buy the original 8 vol. Factory Repair Manual plus bonus manuals & diagrams from Auto Atlanta for around $36 IIRC).
Cheers Mate!
Tom
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