My method with both Heng Long and Taigen Tiger 1s is as follows------ Whichever Tank body you have you will need a Taigen Metal Hull,
Install the two metal plates that come with the Taigen quick release in the front of the Tank one on the body and one on the hull,
When properly fitted one plate slides under the other this allows the body to lock onto the Hull.
Strip the quick release plate down so that all that is left is a bare metal plate and using the provided fittings screw the plate in place across the hull (This is only a temp fit so don't tighten anything )
Goto ---
http://www.first4magnets.com
and order a set of North Countersunk Neodymium Magnets and a set of South Countersunk Neodymium magnets.
Screw a North Magnet in both of the rearmost body locating struts.
Drill a pair of holes in the stripped metal plate at the centre of where the magnets touch down.
Screw two South magnets in place,
You will find that the struts in the body will need reducing,
The magnets are 5mm thick so removing that amount would be a place to begin and bearing in mind you have already reduced the thickness of the metal plate it may well be enough.
My experience is that you will not need any more magnets than the four I have suggested.
You lock in the front of the body to the front of the hull and then lower GENTLY (The Magnets can shatter if you are not careful when lowering the body onto the hull) the Tank Body onto the Tank Hull.
All my Tigers are held together in this way and I have had no problems.
I use Neodymium magnets with all my Panzer 4s but I use a slightly different way of going about it.