I agree with Dave regarding the battery box repair panel.
As far as I am aware TR Bitz is the only manufacturer of this panel.
It is an excellent panel, the patten taken from a rust free TR6, so they
tell me, and fits well.
The only short coming (in my opinion) is that it does not repair the
vertical firewall at the back of the battery which is usually rotted away.
This bit has to be fabricated and added separately.
They have also introduced a lower wing repair panel. Looks good but no
experience on the fitting side.
TR4A CT64306 O