might need some help due to the weight of a freelander but try wedging the spanner and putting vehicle in gear and rocking it to turn engine forward.

They are a nightmare! get some penetrating fluid on there overnight

Don't go down the cowboy route, you'll bust a knuckle, either splash out on the flywheel locking tool or make one.

http://www.landyzone.co.uk/lz/f38/k-series-head-bolts-hgf-tool-info-48856.html

I dont know if its the same as the V6, I made a tool to hold the pulley so I could change the cam belts. Check this thread
www.landyzone.co.uk/lz/f9/v6-cam-belts-change-59563.html

half inch drive air gun usually works quite well, sealey also make a tool that you strike with a hammer and looks quite useful, it is a short bar ,takes a socket one end, swinging freely on the other end is a bar that you hold at 90 degrees, strike the end and hey presto.

I know Northern Irelander might slate me for this suggestion(i hope not) but my wifes freelander is front wheel drive only and i've done it lots of times with no ill effects and knuckles still intact.Do as he says and soak overnight with fluid then get yourself a 2 foot breaker bar half inch drive,spin pulley so when you attach breaker bar it sticks out the front of the car but touches the ground.Then get a mate to put in top gear and stand on the brakes ,whilst you sit forward facing front of car astride the breaker bar and keep a sustained pull on the bar(dont snatch it , it'll never move) it will move slightly before you need to really pull on it . If you pull hard enough it will loosen believe me but like i said it has to be a sustained pull not a half hearted attempt.Obviously refitting is reverse but with your torque rachet. Best of luck and a belated thanks to Northern Irelander for all the advice he gave me last year with the engine conversion.