Well, its in and all buttoned up - a test drive has proven that everything is A OK -gear changes are now very precise, but be assured that getting those two bushes in, for me anyway, ranks up there with installing the heater box under the dash
I used a combination of hot water and silicone spray combined with a touch of brute force.
I removed the actuating rod from the tunnel and filed the edges of the forks to remove any burrs. I left the gear stick attached. I found a scrap piece of 2mm aluminium plate about 5cm x 15cm and wedged this underneath the gear shift rod (that comes out of the back of the gearbox - NOTE this should be in the fully forward position) - this formed a ramp and guide for the forks to slide up and onto the Gear shift rod. Next, I installed the two hot water-soaked bushes and held them in place with a 15cm set on vice grips - lined the forks up, sprayed the silicone and levered the shaft forward with a bit of wood that I had on standby. After a bit of wiggling of the gear lever, the forks slid forward, and I quickly installed the bolt - JOB DONE!!!
So.......thanks everyone for the suggestions, esp the hot water, - without that I don`t think the silicone spray alone would have done the job