Yes it will help and not hurt.
The biggest worry is that they jam and you can't get them all the way off. Ask me how I know...That happened on my old boat.
Then you have to try to cut them. Hopefully they come loose enough to get a saw blade on it.
Don't reuse them
Just got some replacements for my 265 from BoltDepot.
316 stainless 1/2"-20 x 5" are correct. Fine thread. I will have space to add a 1/4" plate in addition to an 1/8" washer.
They also have 316 SS nylok 1/2" nuts and 2"x1/8"thick washers (8-18 SS)
FYI I had 6" on there but the thread was 3" long. The new 6" bolts came with 1-3/4" long threads. Not good. Could not tighten to the motor bracket.
Had to return and get 5". Shit...just realized I didn't return all of them.
One sitting here by my computer...
Yours look long like 6" also.