I want to catch the bus into the wild and let mu body decompose there.
I totally hear you on this. It's sounds great to me, too.
But the reality is, unless you're good at getting far into the remote backcountry somewhere very isolated, chances are better than not that someone will find your remains in a few days at most. For example, backcountry in the national parks in the USA won't be remote enough for you to remain unfound longer than a week, unless you're very strong and good at orienteering off trail, and can get very far from any trails in one of the larger and more inaccessible parks (like Olympic National Park or the North Cascades National Park.) Places like Mt. Rainier, Yellowstone, Glacier, pretty much any national parks or "wilderness" areas in the Southwest USA or California, there's a very good chance your remains will be spotted within a week. Forget remaining unfound or unnoticed anywhere east of the Mississippi. You'd do better in Canada or Alaska, where some of the national and provincial parks are just crazy rugged and remote. It's tough to get very far into them, though.