Help!

My W reg Multi has developed a 'knock/thud/clunk' on changing into second, sort of the same sound as hitting a pothole and in the front offside area, gear changes and clutch seem smooth apart from that and if I make the gear change super smooth with looooong depression it seems to not make it.

Any suggestions?

Check the engine/gearbox mounts, gearbox mount has been known to crack which drops the gearbox, however this is nearside.l
Offside engine mount isn't normally an issue, however check the front suspension arm bushes as well, wear in these will give you sloppy steering and wear on the inside edges of the front tyres.
You might want to consider the DMF but this inside the clutch housing and is more middle nearside than offside.