Mock the seat into position
Here, I've got the bottom of the custom Tack upholstered WiseGuys seat removed to show the blocks I put under the seat frame. This is how the seat is positioned to give the most support under the thighs, while still allowing my dad to be able to get out of the car without commissioning a bystander to pull him out. Now that the seat is in the correct position (front-to-back & side-to-side), we can move on to exactly how to attach the seat to the floor.

Choosing the mounting location
I believe the hole in the plate going from front to back is for the slider on the WiseGuys seat, which we won't be using. We want the seat as close to the floor as possible, mainly for head room. I will be using the lower shaded circle for the mounting brackets.

Here is the bracket I'll be using. If it looks familiar, it's because you've seen it in the exhaust section of our catalog- it's typically used as the frame bracket for our exhaust hangers. Part #21348.

I've bent one of the 21348 brackets to use as the rear mount. The stud I used is one of the bolts that holds the back of the seat on. I put the masking tape on the floor so that if the seat moves, I'll have a reference point to work from.

Here are a few pictures of the front bracket. I used two brackets (actually three if you count the one I cut up for the bottoms) and it turns out they are the exact length I need to support the seat at the correct height.

Here's a bad picture of the same bracket. You get the idea.

From another angle

The rear bracket. I used a bolt that was already there- the one that attaches the back and bottom frames together at the pivot point.

This is the finished rear bracket.

Marking the column location

We wanted the column to come out at the same line as the center of the steering wheel, which is also where we put the wiper. That way, everything will be in line. The only people that will probably notice it are those who are watching this buildup, but it'll still be ambiguously appealing.

Here is the ididit column we're using. It's a 28" steel tilt unit, with a Lecarra Mark 9 steering wheel on there for now. I've wrapped giant Saran wrap around it so that the oil from my hands doesn't make it rust.

This is a tricky part. The firewall on the Bear body is about 2-1/2" thick. In order to put the column through that behemoth firewall, the holes on either side need to be staggered vertically, and also they're not round holes, they're ellipses. We decided to use a 1-7/8" hole saw to cut through, and then clean the rest out by hand. This should result in a very clean looking firewall - there won't be the typical billet floor mount. Just a hole exactly the size as the column. If I'm good.
Column position is a crucial part of the comfort level of the car. If your column is in the wrong spot, it won't tilt properly into position, and it won't be in the optimal spot when you're driving down the road. We established the position by sitting in the car, holding the column up at the bottom, and then marking the top of the output shaft on the tape. The left to right position was determined by dropping a plumb line from the wiper hole center, which is also the center of the steering wheel. It's a bit tricky to get all this stuff lined up, so take your time. It will be worth it when you're comfortable. Oh, and make sure you have THE SEAT THAT YOU'RE USING installed. NOT a milk crate, or a toilet, or whatever else you think might work.

I drilled a very small hole on each side of the firewall, then used a welding rod to make sure I had the holes on the right angle going up to the steering wheel. Then I enlarged the hole to 1/4". This allowed me to use a 1/4" rod, with a flat ground on one end, as a sort of pilot guide in the middle of the hole saw. This will ensure I have the drill on the correct angle all the way through the firewall. I started from the engine side, and just broke through the outside surface of fiberglass. Doing this will protect the gel coat from chipping when I break through.

Here's the other side.

Voila, the slug. We can use this material to insert riv-nuts into to mount the A/C evaporator, gas pedal, etc. without bolts going through to the other side.

A 2" exhaust tube was used as a guide so I knew when I had sanded enough without hoisting the column into position every time I wanted to check the hole. It was tricky, because the hole isn't square to the firewall, and the fiberglass is about 1/8" thick.

I thought I was being really smart by cutting points into the end of the tube, to act as a 2" hole saw. It didn't really work too well. But this is what I came up with- looks pretty sharp, eh?

On to the column drop...