I knew of an autist who was happily working as gardener at a graveyard. Because people are moving much more then in earlier times, you often have graves whose relatives cant take care of the grave on their own. So they let a company take care of it.
So there was a plan for every day, which graves should be taken care of, and a plan what kind of flowers should be planted on new ones, or the gravestone should be cleaned of moss... So he didnt need to have contact with the customers on his own, but got from the office of the company clear written instructions about what graves, what flowers, what kind of work he should do on that day. About half of the day he took normal care of graves like watering existing plants and flowers, fertilizing, remove weed on graves and so on, and half of the day he planted new graves or took care of overgrown one, to remove the old plants completely and plant new ones.
He liked it, because the place was very silent ^^, he was not forced to do the same movement the whole day, still most of the work was of an physical kind and he got clear instructions to do it. Misadvantages were that he had to work in all kind of weathers and in winter there was less work, so he got only payed the half.