Following some of the advise  Here, I have started the laborious task of adding RF bonding straps to the landrover in an effort to help ensure maximised  RF ground plane rather than for noise RFI noise issues as a 300tdi diesel is quite on that front. 4 out of 20 fitted :D

I'm using the stripped braid form RG213 coax soldered to earth lugs to make up the straps. Not sure any difference will be noticed, but will not do any harm anyway.

Had a QSO with a Bulgarian station LZ1NK today on 20m band with me trying to be QRP with just using 5watts and got a 5/6 report.