Not inexpensive, but bear with me:
My '94 is from Canada, where the seatbelt law says the ends must attach to the floor. So it had the "Gen 2 airbag" over the shoulder seatbelts (that had to be changed to the double-rollup into the door belts to import it.) Well, it's back to the Canadian way because at least it only has one rollup reel. Also, look for a "grabbing" type of latch and put it on the belt. The OEM latch simply lets the belt slide through. With the grabbing style, at least the lap belt portion can be tightened and stay tight. However, finding all the parts (rear bulkhead cover, seatbelts, door skin, etc, can become expensive, I'm sure.
I also have 5-points. You don't have to drill holes, they are all already there. Two lap belts (look from under the car to find the outboard one) and the two shoulder belts are on the shelf under the bulkhead cover. Look in the "illustrated guide" area because there are 5-point installation instructions.
To lessen the 5-point hassle factor, consider using velcro strips to link the left lap and left shoulder together, and the right lap and right shoulder belt together. Then when you get in the car, it's kind of like putting a coat on. It sounds silly, may look silly, but cuts the time way down. If you do it right, the latches are already "looped" together, too.