If the neutral switch is OK, it's not too difficult to change out the warning light bulbs; just need to remove the nose-cone (side-panels and mirrors have to come off first, but it's only a ten-minute job).
Only thing you may find is that the rubber bulb-holders can be a bit of a pig to get out; I evenrtually "persuaded" mine with a round-tipped knife blade.
The Haynes manual (well worth buying if you haven't already got one) says
"ease the relevant bulb-holder out of position..."
Ho, ho, ho!
A spray of the connection with a electrical contact cleaner, and a smaear of vaseline or some such on the bulb-holder will make it easier next time.