Please use the workitem json as it is, all you need is to edit the url in Outputfile Arguments and Authorization oAuthtoken I understand there is truncation erros when file sent to you. replace {{yourbucket}} with bucket you created replace {{output.dwg}} with object you put.
{
"activityId": "uLIUN5bLOzQCmoEARUNfG0g1Nr66hj7S.UpdateParameters+dev",
"arguments": {
"inputFile": {
"url": "https://madhukar-fda.s3.us-west-2.amazonaws.com/autocadsample.dwg"
},
"inputJson": {
"url": "data:application/json,{\"Width\":\"40\",\"Height\":\"80\"}"
},
"outputFile": {
"url": "https://developer.api.autodesk.com/oss/v2/buckets/{{YourBucket}}/objects/{{Output.dwg}}",
"headers": {
"Authorization": "Bearer {{ oAuthToken }}",
"Content-type": "application/octet-stream"
},
"verb": "put"
}
}
}