Does anyone have experience with installing thru hull exhaust on a boat that does not already have it?

I have a 1989 Baja Force 235 with the swim platform built in.

I'm looking for any tips or things I should look for. I would like to upgrade the factory exhaust manifolds with ones Gil Offshore exhaust manifolds.

Thanks

i have a set of cmi uni tops with tips.. standard bravo set up.

When you go to drill throught the transom, two tips:
1) drill the holes in the right place the first time! Mount all the exhaust actual parts you can properly, use plastic plumbing pipe / dryer to mock up the fit, then measure all clearances, passages and required locations for the holes.
2) Seal the holes you drill VERY well. I don't know much about fibreglass, but it might even pay to epoxy / glass mat & epoxy the inside of the holes you just drilled to ensure the core is sealed up again.

Good luck mate. Make sure you take pics of the process too! Especially the mock up, if something doesn't look right, post the pic an someone smarter than me will help you out for sure!

A coat of epoxy paint or even resin will seal the holes good.

The exhaust hole cut out locations are standard for bravo drive set up. Make a template off another boat with standard exhaust to find the hole locations.

If you can't go out the back go out the side but watch because it is VERY LOUD