Look man, it's your choice, I'm in Katmandu at the moment just bought myself a Nepali bullet so that I can do it all legally. I've been overland before and believe me they do check your CDP and the engine/chassis no of the vehicle. Iran is particularly thorough and on the Turkey Iran border I have met people who have been turned back for not having CDP.When I drove back the last time they definately checked us at the Waggha border post, there is virtually nothing going through by road and the CDP is the first thing they ask for. Given the current state of Indo/Pak relations I'm not even sure if they allow any cross border traffic between the two countries at the moment. I've been in Pak a few times ( last time 2 years ago) and I have never seen an Indian vehicle of any description. You have been riding around India for a few mths, how many Pak reg plates did you see ? If you really are intent to try this, then don't tell them when you apply for your visas or you won't get them, crossing the Iran/Pak border requires a military escort on both sides, this is a big hassle for both countries which they don't like, if you say you're going overland your visa will be refused. Tell them you fly into Lahore and then crossing over into India. Just think about the terrorist attacks in both countries over the last couple of years and the tightening of visa regulations, do you honestly believe that you can just throw a few rupees at the border police and drive through unhindered and unchecked ?

i did not nead a cdp last year to leave india in a indian mahindra jeep and no probleam at the bordear pakistan dont give a shit about the cdp and the same goes four iran shore a bomb hear and thear maybea it is safear att the kitchen tabeal but no fune JUST DO IT

mahindra jeep ? they probably thought you had army connections
seriously, Don't give border guards a hard time by offering bribes when not asked for, he might take it out on the next rider.