The first pic is, I believe, the tag for the blade made by Britstand( not sure if it's british or Australian made).

My boss just said that it hasn't got brakes  so i assume he means to stop the dozer as he also said all he does is drop the blade to stop

would the serial no. be    A-4JX-690   ???????

The blade no's. are   model = 730      serial = 18DR684

Hope this help's     I'll see if i can get the serial no's. straight from the machine