Hi Ken, welcome to Talk Morgan.
Sounds like you might have what is known as the 4/4 Lowline.
In fact it has nothing to do with being lower but looks lower because it has the wider wings and wider wheels and tyres. (Optical Illusion)
The standard 165 tyres will certainly feel a lot lighter and many people feel that the handling on the 165's with the 4/4 is better and more responsive although of course the 195's will have more ultimate grip at the limits of adhesion.
You will have to be very careful with the wheel offset and I don't think you could simply fit the standard 4/4 wheels as they would foul on the inside of the wheel arch.
You could get Motor Wheel Services to make up a set of wheels to the correct offset but it's not going to be cheap especially if you want stainless wires. Wouldn't harm to have a chat with them though.
I suspect they will look a bit strange with the Lowline Body and you might be better considering a retrofit power steering setup if the you really find the current setup too heavy.
If you do change to 165's, don't fit the Conti tyres, there are several threads in here debating the best tyres and one thing just about everyone agrees on is that the Conti's are the worst option.
