Jim has the "good oil".
It is possible to mix-n-match front end bits, but the only easy way is to use the whole crossmember.
If you have the later series wishbones, uprights and brakes it may be possible to attach these to the original crossmember.
If you can get the whole later series crossmember that your parts came off then it is a bolt in operation.

I believe the stub axles and front bearings are the same so the disc hub should fit to the existing series 2 stub axles, but you would have to fabricate a caliper mounting bracket. Bearing in mind that this is a high stress item.  Hot rodders have been doing this for years adapting late model disc brakes to early Ford axles.  The later upright has ball joints and is not a bolt in swap for the earlier "swivel joint" style.  What you need is the handbook for the later series to see the differences.

Using the donor car approach use both front and rear ends as well as the later master cylinder.  A VH40 power booster is a useful addition.
If you don't use the power booster do not get convinced to use "competition" pads/brake linings.  They will make the brakes seem very ineffective.

In fact for any of our cars it is better to use normal composition linings and replace them as required rather than carve up your drums or discs with hard compounds.  In the Taxi industry smart operators use soft linings and replace them each month when servicing.  The discs last much longer this way and pads are cheap. Many cab drivers are incurable brake riders and can wear out a set of brakes in four weeks no problem.  We are talking of 500 Km every day of city driving.

Keith