Mounting seats

[DJbrand1]

So I picked up a pair of some nice Koenig seats from a local club member. They had sliders on the bottom of them and he pulled them out of an 87 944. I am attempting to put these in my 88 944 Turbo S. Figuring they would go right in. Wrong. So my factory seats have 6 bolts, three on each slider. 1 at the front and two at the rear of the slider. The sliders on the seats bolt to the front holes fine, the rears are off by a hole. The previous owner added some 1/4 inch steel plates and welded them to the sliders inside the tracks, I guess to reinforce the sliders since only 4 bolts can be used with the aftermarket seats. This 1/4 inch plate ends halfway into the hole on the rear of the slider that matches up with the hole on my floor. I guess 87 to 88 changed?? I can't drill out the plate since only half is blocking it, and the bit would just keep slipping right off.

Next, I ordered up some mounting adapters from Stable Energies, because I want to keep the stock seat belt receptacle and not drill a hole in the driveshaft tunnel of the car. Got the adapters, they line up fine except now I need tabbed sliders to mount to the adapters. I order Recaro tabbed sliders. To mount these tabbed sliders to the adapters securely I'll have to use a bunch of washers to get a bolt snug up because there is 1/4 inch gap at where the tabs match up on the adapter and slider. Problem now with the Recaro tabbed sliders, they don't mount to my seats. The sliders that were on the seats have bolt holes 11" apart, the Recaro sliders are about 11 5/8 " apart.

Anyone familiar with what I am trying to do here? Ideally, I'd like to just have the bottom mount sliders right on the floor to mount the seat as low as possible, but since this is still a street car, and the interior is mint. I don't want to drill into the floor pan to keep the stock seat belt receptacle. Hence the need for the wedge mounting adapters which have provisioning to bolt the seat belt buckle to.

What sliders do I need for these Koenig seats. Koenig USA said they would sell me sliders for 80 dollars a pop and adapters for 170 a pop. If the sliders will work for the adapters I already have, that's the only solution I suppose. Any other ideas?