3.5 v8i bad misfire and starting issues

Hi all
recently bought a 1992 discovery v8 efi which had starting problems
i managed to get it started after a few days with jump leads but only ran very rough for about 30 seconds, any amount of revs would cause it to stall and sounded like was running without a couple of cylinders. also when it stalls from running it wont start again and a strong petrol smell come out of the exhaust pipe. i have replaced ht leads, spark plugs, ignition coil, dizzy cap and dizzy rotor to no avail. Im not sure what to do next and looking for a bit of help.

Welcome to the Zoo. Feel free to pop in the Discovery section as there is the place for answers this is just for welcome mat users. Just my ten pence worth, how long has the V8i not been used as you could have fuel blockage issue.

its not been used for approximately 3-4 months but I don't think it a problem with delivery as after it's been turing over and wont start there is a strong smell of petrol within about 2 metres of the exhaust

This was like this when you bought it?
What did the previous owner say had been done to it?

Turn the rotor arm with your fingers. When released it should snap back to its original position.
If it doesn't then the auto advance/retard mech springs in the dizzy bowl have become detached & you will need to reattach them. Can be done with dizzy in situ but I would suggest you pack rags around the dizzy in case you drop anything.
When you pull the rotor arm off you must press down on the reluctor (8-point star thing under the rotor) or this is very common.

I'm presuming Hot wire?

Replace coolant temp sensor - the one behind the easy one.
Compression check on all cylinders.
Remove the rocker covers & turn the engine manually to check the valves are all opening & closing.
Set the timing - if the dizzy has been taken out it's VERY easy to put it back a tooth out.
Check leads are all correctly routed & on the correct plug.

Check for correct firing order and set timing. Important start to rule bigger problems out. Have you checked the condition of spark? They need a big, fat blue spark to run...