Questions-
first off - Is the 1130 enough space for two active adults not to kill each other?
Although not a Lance, I have a 11.5 foot non-slide Bigfoot. My wife and I have no problem. It may sound silly, but just how often would both of you be standing up at the same time? It is uncomfortable to dance. The only time I see a non-slide as an issue, is if one of you has the runs, and the other is standing in the aisle between the person with the runs and bathroom.
2. is there some interior mods for baskets or more space for clothes? I remember seeing one but can't find it anymore.
We have very few clothes that require hangers. Clothes that fold or can be rolled will maximize your storage space. In the closet (and some cabinets), we have clothes, extra towels and other cloth items in plastic boxes (Walmart), so the boxes can be stacked. Shoes also go in plastic boxes. We also use the back seat of the truck, with plastic boxes. We put the dirty clothes in the back seat, in a plastic bag.
3. we will be TCing in the mountains and I plan on adding insulations to cabinets and and outside storage areas. Anything else I can do to help? within reasons and not pulling off the underbelly
I added insulation to my TC. I prefer to use the 1-inch foam board and duct tape to hold it in place if needed. It is easy to cut with a utility knife. Some places require several small pieces pout on place then taped together. The pink fiberglass batting does not have much for R value, so I do not use that. In a couple of areas, I doubled the thickness of the foam board.
I also used the foam used on residential plumbing on all water lines, even those that were not likely to freeze. On the hot water lines, it helps reduce the heat loss between uses.
4. did 2004 include storm/double pane windows in the all weather package?
I can't help you on this question. My TC does not have storm/double pane windows. I use the bubble/alum foil type insolution in my windows when needed. Actually, seldom remove it from the Cab Over and pass through windows. I also have it under the mattress and seat cushions. I store the window pieces under the mattress or cushions when not in use. I cut it for two pieces per window, so I can fully insulate or partial. Although it blocks the view, it is typically used at night, and partially or fully open during the day.
5. Can I use my OEM class IV to tow the toad with a hitch extension?
It depends if you tow with a trailer, or flat tow. With a trailer, I would upgrade the hitch. To flat tow, your existing hitch will be fine. The only tongue weight is the hitch extension. All you will need is an extension with side chains. You probably will need a Tow Brake (about $500). Do a search on RV.NET for some ideas.
I have been flat towing my Samurai since 2005, for thousands of miles. I have never had a problem. I prefer not to tow a trailer for several reasons, especially to avoid the cost of doing it safely.
6. I have bed liner, What else do I need to put TC in my bed. I have read about a bed liner but wondered if insulating sheets would be better. And do I need 2x4 in front of the bed?
I would not use a plastic bed liner, simply too slick. I used the foam for a while, but it would breakdown at the side edges of the TC. I used 2x4s with 1/4s attached, and foam board between. That works to provide support to keep the foam board from breaking down. Overall, I like the Horse mats best, but they are heavy and spendy.
Whatever you use, make sure it goes at least two inches outside of the perimeter of the TC floor. Your TC will rock side to side, and will move slightly. It may be splitting hairs, but by extending past the perimeter of the TC floor it offers more support.
The 2x4 in front of the bed may or may not be required, Some TCs have rubber bumpers mounted in the front, and may not need the 2x6. The objective is to prevent the TC from hitting and bending the front top rail of the truck bed, it bends easily. I prefer the 2x4, to use the entire with of the bottom of the bed front to give the support for frontward movement of the TC. This area is the strongest.
5. Where can I get a pass through window gasket?I can't help on a source. I have had them in the past, years ago. I can honestly say I found them of little value. Most of the type that allowed you to open and close the window would rub the paint off. The type that was permanently mounted would not allow for opening and closing the window, and create greater requirements for heating and cooling the TC. The alignment of the truck window and TC window could also be an issue. I would not install one today if it was free.
If your TC does not have a switch for the water pump, I would suggest installing one. When you are not in the TC, you can turn the pump off. In my opinion, especially fulltiming, an accumulator is very valuable. The accumulator allows the pump be off, and depending on which accumulator is installed, you still have about 1 gallon of water. especially nice at night when someone uses the bathroom. I used a Home Depot Accumulator.
If you will not have shore power, I also suggest changing all lights to LEDs. I prefer the flat boards, much cheaper. I highly recommend a Wave3 heater.
You have ask quite a few questions of which you may want more details on. I suggest you break them down, and start a new thread with questions on the same subject in each thread. Some of the questions would be best answered in other Forums, such as Tech and or Towing. I think you will get more in depth answers. Do use the search feature, lots of info there.
Wayne