As this has been asked a few times on different threads.
I thought we'd gather it into one thread debate it then try and get it down into one document and put a sticky on it.
HG swap on a T16 is not rocket science, despite what some people say.
If its your first one allocate a weekend to get it done.
No special tools required for just the head gasket job, what you will need and may or may not have:
Torque wrench 30nm - 200 ish nm cheapo jobbie from screwfix or machine mart will do, about £30.
Good quality 15mill hex socket for the head bolts.
Decoke brushes.
3/8" 8 and 10 mill sockets, 6 and 7 mill for the jubilee clips (better than screwdrivers).
22 mill spanner for the fuel filter, 1" spanner or pipe wrench for the master cylinder vac pipe.
Can of lighter gas x 2, can of plusgas, wd40 or duck oil.
Carb cleaner or petrol and a bowl from the poundshop for cleaning bits.
Loads of rags and newspaper for your millwall brick.
3 sheets of 1000 grade wet n dry and bit of 2x4" for block cleaning.
If you're going the whole hog and doing a valve lap and valve stem seals.
If you're lucky stem seals will come out with the long nose pliers, unlucky you'll need a remover about £10.
Valve spring compressor, double handed jobbie about £35, you could probably hire that for the weekend for about a tenner.
Grinding paste and plunger any motor factors or halfrauds £5 ish.
Alternatively Gunson's (
http://www.gunson.co.uk/acatalog/index.html)
Eezilap £25.