Thanks again MMWJR,
I spun the prop while moving the handle forward and would engage occasionally with the rest resulting in clicking.. With reverse, it locked without any issues.. Doing the same test with the gear cable in my hand and spinning the prop it would lock every time I pushed it in...
I did a shift cable and gear cable adjustment using this video..
and it now locks every time.
Important thing to note: When I did the barrel adjustment on both cables .. it still had the same issue as before however I needed to move the stud from the lowest position to half to engage a full lock on both forward and reverse (5:06 on video above).
It now works on trailer without any issues.. The important test will be out on the water.. Hopefully next weekend if the weather is good..
Many thanks again! How many beers do I owe you for this one?