Anyone have a simple way of accessing the alternator on a '92 Hiace with 3L diesel?

Thanks.

Simple way? Somehow I remember it is possible to see alternator if you remove the right front tyre but really no chance to try to reach it. The space between there everything is too small for my hand.

Times that I had to access it, the method was remove right seat (In your case, the driver's seat, Rhd I suppose?)
You have the engine hood open and right side to it there is small additional cover with x-number of bolts holding it.
The job is much easier if you have (cordless)electric drill/pneumatic drill to open those bolts.

Thanks for the photos. I talked to mechanic and he showed me away to get at the wiring without removing the seat. I just need to access the wiring to install an isolator for my house battery. I might still go at it through the right seat because it looks like I'll have better access.