I have an older (1972) H-16 in excellent condition and I want to upgrade the rigging to a 4 line trapeze. The current mast tang is just a strap about 3/4" wide with one hole for the shackle. All of the parts guides and manuals show a larger tang with three holes - one for shroud/stay shackle and 2 for the trapeze shackle. Should I change the tang given that there will now be about 380 lbs hanging off the trap wires? The mast tang is not cracked, but it is bent down at the bottom most point and pushing into the mast a bit.

There's a reason the mast tang design was changed.

The original tang design was carried over from the 14, which didn't have a trapeze then.

Short answer - get the new tang. You won't regret it.

Thanks! Now a quick question about changing the tang - does the Hobie mast tang come with rivets? and if not what type/size rivets would you recommend?

I don't think the tang comes with rivets.

3/16" stainless, medium length. Use rivet sleeves to maintain watertight integrity of the mast and a thin layer of silicone to prevent electrolysis between the tang and the mast.

You'll want an industrial strength rivet tool to pull those rivets. Even the "heavy duty" ones they sell in most hardware stores are not really up to the task.