Got an 18' Proline center console sitting on a trailer with problems. My
trailer has the old classic two pieces of 2/4, fore and aft, parallel,
approx 3' apart, that the boat hull rests on. One thing is my vertical bunk
supports are corroded to the point of needing replacement. Two are badly
enough corroded that they look they would collapse if I hit a bump while
trailering along. Looks like I'm going to need to replace 'em at the house
in my driveway.

My question is whether or not I can get away with doing 'em one-at-a-time.
I'm going to have to chisel a few of the nuts, as they're so badly ate up
with corrosion. Others I'll have to loosen with an impact wrench.

Is my hull weight likely distributed enough that I can remove and replace
the vertical bunk supports one-at-a-time? My only concern is that if
there's any appreciable "sag" when I loosen a given bunk support, then I
might end up with new one being a couple millimeters lower than it was.
Let's say this happens on all 6 vertical supports. Does that present any
significant problem. Doesn't seem so, but would appreciate hearing from
guys who've "been there, done that", and can tell me if I'll probably be OK
..

Besides which I really don't want to put the trailer back on the streets
with thos support like they now are.