Heat Man Screen 3 - Part 1

Zipping

Do not drop off the ladder when entering screen 3. You can hold down in the screen transition to grab the ladder if you press A to drop down the ladder. (You can also set up the zip from the floor, but it takes several more seconds.)

There is a very specific placement of item 3 from the ladder, against the left wall, for the optimal setup.

Stand on the left edge of the item 3, so Mega Man is mostly under the ceiling, not the ladder gap. Wait for Mega Man to suddenly move above the screen, then execute the A-Trigger Zip (https://goodboyrush.net/books/mega-man-2/page/zipping )

Zipless

The strategy for Zipless relies on using Item 2 as a platform, while keeping enough energy left over to fly across the disappearing block gap (in screen 3 part 2).