yes I have done one
tips leave yourself a weekend to do it comfortably.
i left the tank in but the choice is up to you. i did try the drill out the spot welds with a spot web drill bit but blunted a few drill bits and there was that many that i went for the grinder instead :!:
What we did was work out where the ridged and non ridged floor pan cross members and then mark them up. then grind out the floor but keep the cut about 1" from the edge of the floor pan. with the edge at the top of the floor pan under the seats we used a dremmel as it was less agressive and we were concerned about what was under it - if you remember LROi they cut through the brake cable when they did there's. later on we then used a cold chisel to get git of the left over floor pan.
you'll probably find the floor does a bendy thingy when it comes out due to where it rusts over the ridged floor cross members.
There is a picture in my 'my space' link that shows the floor pan out.
whilst its out, chuck a bit of light purpose oil down onto the A frame ball joint, pressure wash all the smeg off the underside that you can now see and hammerite everything
we welded the boot back in with a seam weld all the way around and rivited the floor to the cross members.
think that about all 8)
