It does bolt up directly but only to the head. the exhaust will not bolt to the turbo and the turbo will not work with the ECU. you must convert the turbo to boost regulated vs the vacuum that it has on it now. it's not an easy task but it can and has been done. you need to either convert the VTN turbo you have from the ALH to boost controlled and you will need a tune for that or it will run like a dog with 2 broken legs, OR you can go the complicated path of changing out the n75 and running vacuum for it with some complicated bits. the tune alone is $300 but IMO you can get a used turbo in good condition for less than that for your 1.6 OR just replacing it for about what $500?
I guess the fuel injection pump off a 1.6D turbo could work for the extra supply of juice. If then, sourcing a whole 1.6D turbo upgrade would be a simpler solution if I didn't have the ALH going in. I'm already knee deep in performance parts for that motor.1.6D has no computer. The turbo will physically bolt up but the non-turbo mechanical injection pump will have no idea what to do with the extra airflow and not supply extra fuel to yield more power, and you won't have any ordinary means to control the variable vanes of the turbo.
At minimum, you'd need to swap out the vacuum-actuated can for a pressure one and devise some sort of manual boost controller. The injection pump can be modified or swapped for one from a turbodiesel that has an aneroid to use boost pressure as a fuel enrichment control input. There's lots of knowledge in tuning the earlier VW IDI Diesels (turbo and non-turbo) but few of those guys (still) hang out here. However, the ones who do have shared some neat tricks at adapting the VNT turbo without a stock ECU and there's a highly regarded (but expensive) source of modded mechanical injection pumps that extract a lot of power for IDIs and m-TDIs. Look up the "Giles pump" and check out vwdiesel.net