the conversions you see in Pakistan on facebook and other social media fall into one of the following categories.
1 - rolling project forever as the shop doing the conversion didnt care for new screws or sealants, or even parts. - they literally even reuse old scrapped wheel bearings.
2 - these are chop shops and have some stolen/robbed VINs in their possession and when you need new parts for any repair - you may land into trouble as MB-AMG, BMW-M and AUDI-S are not usual cars but very expensive leisure toys - hence have a lot of fluff attached to it - all the way to being flagged at the original data repository when a new download is required (A very recent case in Pakistan has got someone into extreme levels of pain trouble with a Mercedes E55 AMG - W211 chassis)
3 - Sourcing repair parts for these cars become a nightmare as you carry two VIN/Serials for the car. One is the one that is stamped on the unibody and one from all the modules, you cannot rewrite VINs willy nilly unless its some useless part like an old LKM which only takes the last 7 digits, the other parts become problematic - e.g. writing a BMW-M VIN to a diesel variant will result in error as it will look for some RPO codes and required modules too.e.g. BMW Aktif-Lenk was available as an option on E70 even with M spec, but all M spec had the same LWS module which doesnt fit the regular models.
And god forbid - if the VIN is hot, then you need to source parts with some other similar VIN.
Funny issues in Pakistan follow down,
ask someone owning any BMW NG6/NG8 engine in Pakistan about replacement water pump, 99% answer with "scrapyard" which is worthy of LOL. - While a new replacement pump and thermostat kit cost about 480USD which in todays rate is Rs 90,000/- and hope the mechanic knows what a torque wrench is as the aluminium bolts are one time use and need to be stretched properly.
we all know that the electric water pump will fail at early date if the coolant was not changed in time or if the oil filter housing gasket was not attended to and the coolant has some oil in it. It swells up the pump internal seals and damages the motor.