I have a wooden Merlin NSM IV and want to make her really competitive. Has anyone got a deck stepped NSM IV and is this competitive against a Tales?

I love the boat but don't have 5-6k to spend on an upgrade so may be better off spending 2-3k in making this boat more competitive. Currently has Hog stepped Alloy rig

Short answer is no and the long answer is still no. Spending the 2-3k
Needed to convert to deck stepped will simply be money down the drain and will not be reflected in the future sail price.

Also you can only convert if your nsm has a low bow tank rather than a high bow tank as hull does not have enough strength to take the rig loads generated by deck stepping.  Low bow tanks came in with about 3200 but some after this still had high bow tanks.

Better to spend the money upgrading to a wooden tales.  There are some good ones on the for sale list and they should have been expoxied from new so maintenance much lower.  Also previous owners may well have spent the money on carbon spars.

James, Richard is right I am afraid. It is simply not economical to deck step and carbonise an NSM 4 in order to try and compete with newer designs. You could most likely get £700 for your boat, add the £2-3k you were going to spend and buy a wooden Tales or a Make it So. They will be much more likely to hold the value and will be competative with the back - mid fleet of newer boats.

don't bother.
Enjoy the mature boat.