Reading SD Card output to CANbus

My project is to read data from an SD card and transfer it to a CANbus interface module MCP2515.
I use the SD.h library to read the data. It has 10 fields. An ID, a data length number (always 8) and 8 fields of data payload.
Here is an example: 89F80173 8 4C 1 D6 EB 90 CD 1A 5A.
The fields are separated by spaces but I could change the SD source to separate the data with commas (,xx,yy) if it helps.
My skill with programming is limited so I ask for help to code this transfer of data.
The data needs to go to a STRUCT already defined as:
ID = 32bit unsigned
Data length = 8bit unsigned
Data = 8 x 8bit unsigned
I can read the SD one line of data at a time and store it in a buffer. Now, how do I move that to the STRUCT so I can then give a 'send' out to the the CANbus?
I would appreciate any assistance.