1987 B250 questions

I got an '87 B250 van (5.2L V8) from a friend of mine and it has a few issues that I need some advice on.

Here's the backstory: The alternator went out on the previous owner and he didnt really use the van often so he didnt replace it and let it sit for about a year straight. Then he gave me the van and I put a new alternator and battery in and it started right up and ran surprisingly well.

Here are the issues:

The gear indicator on the steering column is stuck on park.
Usually the van wont start in park so I have to shift it to neutral to start it.
The van rolls in park.
When the van is cold the transmission slips.
The transmission appears to have a small leak on the front seal.
Could these 4 issues be related? Are there any simple things I could do to resolve some or all of these issues? Are these issues serious?

Also, the van appears to have an AC compressor but it doesn't work. If I remove the compressor will it improve my gas mileage any?

One last thing. The van has 4 captain chairs but I would like to replace the 2 rear chairs with a bench. Does anyone know If I can pull out the chairs and pop in a bench without having to drill a bunch of holes?

THanks!

-Adam

Hi, all I can say about your van rolling is that I have a 94-b150 that I bought awhile back. I placed it in park and it would roll back in reverse. I called the dealer and asked if that year had transmission problems. They told me no. They looked at it and found that I was missing a bolt or washer on the linkage on the transmission. Never has rolled since. Good luck on your other problems.

Did you get it fixed at the dealer? About how much did it cost?

Honestly can't remember what the fee was--wasn't to much. I stopped dealing with the dealers as far as fixing my van. Their twice the amount as any other mechanic. I belong to three AAA's. And try and find a certified three AAA's mechanic. I find them more reputable and honest---as to the dealers their trying to make you buy the car twice over and then some...Good luck.

Do you think this is something I could do myself?

I'm no professional mechanic but I do know how to turn a wrench.