Yes, it will fit just fine.
Certainly, they are both YJ"s.
Depends on if it's a strapless style bikini or not. 87-90 Wranglers used a different style of rollbar, so if the bikini just goes from the windshield frame to the rollbar and wraps around, it will work.
How do you change the steering shaft in a 1990 Jeep Wrangler?
The amount of oil needed for a 1990 Jeep Wrangler is 6 quarts. The Jeep Wrangler uses 10W 30 oil.
Yes.
No.
I shouldn't, 1990 is a YJ and the 97 is a TJ.
No
You want to look on the intake manifold on the Jeep Wrangler.
The correct factory tire size for a 1994 Jeep Wrangler is 215/75R15.
No.
There is a subwoofer in the center console, 2 speakers on the rollbar, and 4 in the dash (a tweeter and woofer on each side).