Disclaimer: MINOR tweaks to make these trucks having a point at all. Do not expect something highly buffed or "can do anything without consuming fuel using AUTO".
Boar: Changed from MEDIUM Tires (as e.g. the White Western or Step300 has) to HEAVY Tires for that 20 ton truck. Fuel increased by 100l to 400l. Engine, gearbox, steering angle and center of gravity unchanged, that felt OK. Shall now be better in mud than the DAN, less good than the KOLOBS. Warning - peak fuel consumption can still hit the 30 l/min mark as its vanilla counterpart offers.
P512: Some minor tweaks.
Fuel Increased to 300l, a buff with 350 may follow as I still try to find it position in the US line. Which are missing a "long range hauler" with a decet range. This one having no AWD but saddle high/low/logs and trailer access may fill that role. Steering angle increased to get more agility. Center of gravity for cabin lowered by 30 cm to have its tipping behavior on par with other trucks of the 10-14t weight class. Added a set of chains to have it a use in Alaska. Mud friction of these chains down by 30% with respect to stock "non-chained" tireset. Engines & gearbox unchanged. Added some few spare parts to the storage boxes if you install a spare wheel. I rarely see the diff while driving 3rd person - so I take some gearbox damage from time to time. Still not a dedicated long range hauler, but also not always on the way to the next petrol station. I may buff the fuel with one of the oncoming updates.
Both are mostly MY interpretation of making trucks having exactly no point in gameplay "as shipped" somehow work. Not easy, but also not for masochists. Both vanilla trucks were a bit usable on the first Michigan maps for logging and thats it. Waste of work. Both trucks had not any strongpoint rather than "its new with Phase 3 update". So I think plainly from gameplay point of view - the Boar can be a nice "heavy" RU logging truck between DAN and KOLOB, the P512 could develop to a US long range hauler (kind of poor US man's AZOV 64). Both are still not exactly happy about serious mud sections. As both struggle either with lack of AWD or a severe fuel consumption to pass. So a clean driving style as well as meaningful use of the gearbox and AWD/Difflock to keep fuel consumption as low as possible is required to make the trucks work. If you do not want to do that - use an AZOV 64 or Tayga.
I assume these tweaks will also work in Multiplayer as the size is about 1 mb and thats mostly for the "shop pictures".