Microswitch woes

Having a few intermittent faults with my doors just lately. The interior light has stopped working on my drivers side front door, unless I open it really slowly, where it flickers on and then goes off. After a bit of searching I found that this was probably down to the microswitch in the lock. It also seems to be affecting the opening of the boot, with the boot not opening on the handle unless I have opened another door first.

Can anybody advise me on how to get to the microswitch? I can't seem to access it without dismantling the door as I cant even see it. Spraying wd40 into the lock mechanism hasn't helped. Is there a quick fix I can try without dismantling the door or anything else I can try?

Thanks all