would it be easier just to have a driving test rather than go through all that BS paperwork, check out the way Thai people drive, the test couldn't be that hard
Aside from your question be sure that you get stamped in for 60 days by giving the passport opener at your visa page, we recently came through immigration and got stamped in only for 30, both of us.
open a thai bank account then transfer the money from your gb account in gbp, I have found the thai bank with the best xchange rate to be thai farmer bank, £600 to transfer is a ludicrous ripoff, it is also easy to send back to an os account, best of british luck