I've done two transom repairs with seacoast
http://www.transomrepair.net I would highly recommend it!! I used a chainsaw and welding a chisel on the end of a 3/8 rod so I could scrape the transom clean. Took about 2 hrs to clean out the transon. Gotta be real careful not to go too low. I cut my transducer wire by accident but if that's all that went wrong no problem. ha Then I used a heat gun on low for several hours to dry it completely out. One of the things I did I was soooo glad I did was make myself a wedge shaped funnel to help guide the stuff down the transom. It would have been a COMPLETE mess otherwise! I had my son hold the 'funnel' which was a huge help! Bump the back of the transom with a rubber mallet ever so often to make sure it settles down. This stuff is STICKY!!! I also used a 2by and clamps to keep the transom nice and straight. Had I not down this it would have budged out I think. I found a pc of 'U' channel aluminum on eBay to cap it all. You will notice it get warm,,,, then HOT!! You have about 1/2hr working time. Mix in the shade and keep the stuff cool the night before aka in the shade or whatever. Makes a big difference on working time. So how good is it? Well I put the engine on by the afternoon and could jump up and down on the engine with ZERO flex in the transom. But the real test was a year later. I hit a rock going 15-20 MPH. Engine flew up and bounced back down. HARD! Didn't even faze the transom. Still solid as a rock. I really don't know what more you could ask for. I highly recommend the stuff. Worth every penny. Nice people too any questions they are real people ready to help.