Best thing to do is start practising. You might be able to teach yourself with a bit of reading up on the subject too.
I've had my landy for about 3 weeks and have been cleaning her up a bit so i can paint the chassis.
first i found that the rear cross member is rather rotten at the rear.
Then found out that there is a hole directly above the front axle on the drivers side.
Gearbox crossmember has a huge hole on one end.
Last night went to fit a new rear bumpstop and created a 2 1/2" square hole with a screwdriver directly where the bumpstop covers.
It's been patched a few times already and i'm thinking about a galv chassis over the winter.
The bulkhead is really good apart from the footwells which aint a problem.
Amazing what the mud hides.