Replacing Battery (Standard method)
Fitting the battery is a pain. The cross brace that has to be loosened on the outboard end then unscrewed from the access panel is actually the fender brace so don't discard it in a fit of anger. Plan on using some penetrating fluid on all threads before starting the project.
Replacing Battery (Alternate method)
(Anonymous) actually fitted a battery that could be dropped in from the top. It does require removing the voltage regulator and the hood latch, but that only takes a few minutes. Lifting the battery in and out from the top (with a battery handle) is much nicer. ****However, so many many people have destroyed their self levelling headlight control (which is no longer available and cost about 20 times the cost of the battery) that the time saving cost them dear. Don't do it. If you do some preventive maintenance by greasing the bolts on the battery door area, using the correct method is no great pain.