Mike, for the 53 SR400 tanks, if you go to the original link posted you will see a picture link for the non ultra realistic bikes. Click on that link and then click on the SR 400 link. On the SR 400 page near the bottom is a picture link of some tanks and a big SR. Click on that to get to the page with the 53 tanks and the assembly instruction pdf link which is in the white triangle near the bottom. The instruction pdf link is the blue button with part1 on it.
Here is the page with the tanks:
SR 400 Tanks