No, galvansied chassis became standard for MY '99, which equates to somewhere around Oct '98 in cars first coming from production.
At the same time, the bulkhead was shortened - it was a requirement to meet EU rules for the fitting of Airbags IIRC - which also lost the air demist as there was no longer room for dash top air vents (so the electrically heated screen became standard too). The new short bulkhead was made from stainless steel, rather than mild as previously.
The easist way to accomodate the increased door space was to amek the doors 2" longer.
I no longer have my '98 +4, or I could have put it and my 4/4 side by side and you could see the difference. TBH, unless you know what they look like, it's not obvious...
Come to Castle Combe - I'm sure we can find a selection to give you an idea of the differences.
Home servicing should not be a problem BTW, particularly if he has a folder of receipts for all items purchased...
