Installed a SeaDek pad on my 270 - it was a fairly painless process.
1. Template with markers and instructions sent straight from SeaDek.
2. Taped and outlined swimplatform pattern - sent it in for test template option.
3. Received test template - verified and approved for final cut.
4. Received final cut/product and installed per instructions.
Back and forth with templates was a little bit of a pain but turn out pretty good!