Tunnel to seat box woes

Last night I got around to dropping the 300tdi tunnel into the defender, but it appears for all the world as though it's too short? I've got roughly 1/4 inch gap at the rear between the seat box and tunnel, and the same at the front where it meets the bulkhead.
On the surface it seems like minor detail, after all it's a land rover, but this morning I can see quite a bit of daylight in the lower corners between seat box and the bottom of the tunnel and also lower front corners.
If I simply slide the tunnel back tight to the seatbox, the holes along the floor don't line up and obviously there's even more daylight between the tunnel and the bulkhead diaphragm.
Have I done something wrong? Is the seatbox position adjustable front to back? I would have thought I'd got the seat box right as it's up nice and snug with the rear tub and sealing tape.
I'll try and take some pictures tonight to show where I'm struggling, just hoping someone with more panel work experience may have come across this before.

pic?

Will of when I get home.

mines the same, I hit a ditch in the bad weather and have done a partial strip and rebuild, I have a the same gap where it meets the seatbox, also looks like the top screws have burst through the holes, seems to be standard on mine and a mates 300tdi 110,

nothing to worry about, just LR build quality I guess,

Know exactly what you mean, the top holes are more like slots, but the tunnel was like this when I bought it. I was just planning to fill the daylight gaps with some black silicone but thought it best I check first, just incase id got an alignment issue.
Aside from that, the floor plates and everything else line up pretty well really. Just wish I knew someone with a 300 or td5 I could have a poke around at.

yep that's it, I thought I had done more damage than I could see, but everything else lines up fine!

thats fairly std fit for many, without much work you wont make it much better

That's great then, if it's normal to you sir, it'll certainly do for me