Thanks to all so far for the recomendations and advice.
I can see that the loadspace will be affected by wheel arches but that does not stop me putting a frame work on either side of the van so that traction wagos can be placed upsida down accross the top of the engine. There may need to be wheel removal or something but I think it will work.
With regard to Andy's comments about the Jumbo Transit this is what lead me to the 17 seat minibus. Beolw are the important weights and are based on a twin rear wheel vehicle hance the narrow width between the wheel arches. there is a single wheel Jumbo van too.
Gross Train Weight 6150
Gross Vehicle Weight 4250
Minimum Kerbweight 2712
Payload 1538
Load Space Width Between Wheel Arches 1153
this is the Iveco 3300 WB Van data, 1.9 tonne payload so I would be concerned if this is the same kind of van carryng a 2.2 ton miniature!!!!!
Gross Train Weight 7200
Gross Vehicle Weight 4350
Max. Towing Weight - Braked 3600
Minimum Kerbweight 2410
Payload 1940
You will note that both of these vehicles are heavier than the 3.4t range but accoding to my driving licence I am OK with one this heave and a caravan - my particular licence credentials allow me an 8250 gross train weight with a trailer.
Time to carry on looking
Brian