Apologies for the delayed reply, was stuck with some work issues. The Quetta Collectorate's clearing certificate and duty payment receipt in original should work. It is the job of Excise to gather the vehicle engine and chassis number verification certificate from Customs after receiving an application for registration. The application for vehicle registration would be routed to AO (Verification) of the respective Collectorate who would issue an internal check certificate. Also, out of curiosity sake, how much did the vehicle cost you and how much is excise costing you?
Hope this helps. Please feel free to put up any queries.
Fahad Bashir,
Assistant Collector, Pakistan Customs Service.