I've made some changes in mine recently. I removed my rear seat and built a truck bed style tire carrier onto my existing high lift mount. I think it turned out pretty well.
Horizontal tie bar between the two lay-downs for a bit of structure and somewhere to put my ratchet strap that holds it in place:
Hopefully you can see what I mean by "lay-downs"- just the bars bolted to the under seat cross member. The jack is attached by bolts that were welded through the tubing to hold it in place. Their size escapes my memory:
The feet to hold the tire above the tranny tunnel and the 2x2 angle I used as the floor mount. The angle is bolted to the under seat cross member. It worked perfectly as a strong, easy mounting point:
This picture got skewed it would seem, but this is a general overview shot showing how the tire just rolls out of the back doors with plenty of clearance and it's much easier to get to now. My amp tucks nicely under the jack and I re-mounted my amp from the back seat to the back of the box:
Looking out of the back, the tire doesn't interfere with my line of sight at all:
And finally, the back cargo area as it is now. I found a nice, waterproof, locking plastic container at K-mart on sale for around $20. It's great, and holds everything. I keep my tools and recovery bag in the floorboard behind the passenger seat for easy access. I keep everything else in the tub. I still have plenty of room on the sides, and could stack stuff on top if I need too. I'm going to be getting a smaller tub to go under the jack/tire carrier behind the passenger seat next to the amp to hold food and the like:
Annnnd that's that. Took me about 2hrs because we were moving slow and messing around. I really like it. I never used my backseat anyway, and having my cargo area back without a rear tire carrier is nice.