Jacking point for coachman

Hi

I need to take wheels off to change the tyres.  There is no Jack with the caravan 

Handbook says to jack up on axle but with a car jack this isn't viable hard to reach and the mover is obstructing access.  I have two axle stands for support while taking tyres to be done .

I am wondering if its OK to use the main strut of the chassis close to the centre I can get?

Also is a car jack inadvisable?- all I have