stay away from such scrap,
Military / Govt auction vehicles are sold with a DNA - date on import papers & date of induction / decommissioning from service. with engine & chassis number mentioned over auction payment challan which act as receipt of SALE, for excise department. such vehicles can be registered against those chassis / engine number and engine swaps can be altered later on.
an scrap vehicle with no such DNA record can not be registered. either he purchased it 'dubiously' n / or have sold the papers & plates at premium price to someone else
Taxes & token start from day of fresh registration by the Buyer.