So much is said and written about the K-series and HGF that it is almost impossible to tell the wisdom from the "fake news"
Personally, I keep it simple - I have two mid-90's K-series (1.8 MPi both) with completely standard thermostats and cooling systems, standard elastomeric head gaskets and the standard baseplate/ oil-rail. Neither have had a HGF despite 100's of thousands of miles of loving abuse (track days/ sprints etc etc) in the back of MGFs.
The two things I do are:
1. Avoid reving the engine over 3000rpm until the engine is fully warmed through
2. Keep the heater on max until the engine is fully warmed through
Both of the above is easy on an MGF where you can see the oil temperature, and with the roof down, chances are you want the heater on max all of the time anyway (we live in the UK afterall! LOL)
In a Freelander, this would not be too hard - leave heater on max until it starts pumping out piping hot air - and same with the rev limit.
Why should these make more of a difference than anything else?
Item (1) is as much about mechanical sympathy as anything else - but also about the coolant circuit design and its limitation. To maintain flow rates and pressures, the bypass circuit is of a particular diameter. The water pump is mechanical and very efficient, shifting a surprising volume of water! Mash the throttle with a closed thermostat, and there is not adequate flow reserve in the bypass pipework (which has been known to collapse under the load of the water pump!). This is why Rover Powertrain designed the PRT - it opens under pressure to mitigate this problem.
Item (2) keeps the heater circuit open - and increases the capacity of the bypass circuit. Again, it speaks to the water flow problem during times that the thermostat is shut.
You can go for all the expensive technological solutions. Or you could simply be disciplined with your right foot and turn open a heater valve. I've gone for the latter.
MLS is only ever any good if you have a liner with a couple of thou' stand proud form the deck height of the block. The vast majority of K-series were manufactured before MLS, and the OE spec was for the liners to be flush with the block. The elastomeric liners are fine - and if you warm the engine consistently (see (1) above), the block/head shift problem is markedly lessened and not a problem. And these gaskets seal the fire rings far more effectively.
MLS is a godsend where you need the shim to rescue a dodgy cylinder head - so they're not a complete waste of time.
Stronger lower oil rails are of doubtful significance. Even the folk at Powertrain were doubtful of their utility, but the modification kept Ford, Land Rover's new owners, happy.
Other than that, keep on top of maintenance - cure any leaks (very small reserve coolant capacity in these engine to ensure rapid warm up and reduced exhaust emissions). Do a good job, and you'll have a very reliable engine