Newbie, hollowing out 2002 ex-airport shuttle for cargo/camping

[Per]

She just passed 200,000. I got it as an emergency for $1600 when my other car died and I was in a rental.

 

My questions are

 

1)"What is preferred way to disconnect rear HVAC unit by driver's side rear door?" Hopefully so front HVAC still works. Gonna be a pain to do it so AC still works? Is the disconnect gonna allow bad air into AC plumbing, break all sorts of AC recovery laws, etc? Can you tell me off the top of your head what size hose I might need to 'short circuit' either heat or AC?

 

2)When I was rudely ripping out head liner, plastic door coverings, etc I think I enabled Child Safety locks on double doors on side and rear. On side its the front door that opens 1st with handle on face of door that wont open from inside. I can make it open by grabbing the connecting rod to tripping top latch.

 

On the rear its the driver's side that opens 2nd with the latch that is covered when the other door is closed. I can open but grabbing both upper and lower rods.

 

How do I fix or disable Child Safety feature?

 

3)How do I remove the 3 steel rails on the floor that used to secure the bench seats? I've heard of people doing a lot of cut off wheel and grinder work because they can access bolts underneath due to some aluminum heat shield. Can you just remove the shield?

 

4)This van is a base model, no power windows, no reclining front seats, no cruise control. Are any of those easy swaps and upgrades from the junk yard?