The Tatra factory in the Czech Republic has for a long time been building heavy cross-country vehicles. The Tatra 813 8 x 8 heavy truck has been built since the late 1960's. It was used by various Warsaw Pact armies, as a truck and as an artillery tractor. It also served for many civilian purposes. With its excellent cross-country mobility, it is also a favourite at truck trials.
Wikipedia has more information about the original.
Luke Ueda-Sarson has a web-page about modelling the Czechoslovak army. The chapter about artillery has an example of a finished model - scroll down to the middle of the page. Micro Armour Mayhem also has pictures of finished models.
This items consists of 4 models on a sprue. A canvas roof and a bulldozer blade are separate items on the sprue. To mount the dozer blade, the towing hitch (coupling) on the front fender must be removed. To mount the shovel, cut the shovel and D-shaped sprue from the main sprue and glue it under the cab, right back to the chassis rod - see the 3D sketch