The head has to be removed on the 1993 Roadmaster to get to the gasket. You will need to remove the intake, exhaust manifold, and valve cover then unbolt the head to remove it. Check the head for warpage while it is removed.
Which solenoid? BOB
gmac05062023a
Solenoid
Remove the grill
Remove retaining nut
Oxygen SensorOxygen Sensor Location
Not without serious modification, but anything is possible if you have enough money for a conversion.
Replace ignition switch for 1993 buick century?
Bottom of engine, inside the oil pan.
Remove the fuel tank to gain access to it.
I have used regular "87" octane gas in my 1993 Buick Roadmaster for 7 years and it runs like a top. I don't know the gas mileage as my odometer doesn't work, but it seems to be OK.
Remove the crossmember and drop it out the bottom no problem.