H.I.S.S. Instructions:
The white vinyl-backed prints will look immeasurably better if you protect them with a layer of packing tape.  Before you get started, just pull off enough from the roll to cover the entire line, and apply over the stickers.  Rub out the air and use your nail to smooth it out.  That is important step number one. For the circular stickers, you should take a circle stencil and draw perfect circles on the reverse side of the stickers.  I find the easiest way to do this is against a window, drawing the circles on the BACKING.  This way, you've got a nice guide to follow and cut them out perfectly.  Do this for the "3/63" and all the cobra sigils and then cut out all your circles.  Move slowly and don't hold your breath.  For the white-backed sigils you are going to cut out square or in straight lines, cut as close to the printed surface as possible.  In the case of the headlights, you want to cut those out ON the lines. 

Now for second important step number two.  The white-backed stickers are printed with a black background that, once you gloss them with the packing tape and apply to the black HISS, will simply appear to be glossy clear stickers.  The one thing that you must do to every sticker being applied to the black areas is take a black sharpie marker and line the edge of the sticker.  Hold the sticker by the front and back and use the side of the marker tip to quickly go around the edge.  If you hold the sticker so the tip slips off onto the backing and not the front, if you do slip, you will only mark the back and not the sticker front.  You MUST do this step because the white vinyl is white all the way through, and if you do not black out the sticker edges they will show a super-fine white line around the edge, the amount they are raised off the vehicle.

Once you have done the "blacking out" the stickers are ready to apply.  Smooth them on good and get out all the air.  The tape will protect them very well. Oh, and the last thing you should do after the vehicle looks all nice and whiz now is wax it.  I did my mine with "Future" floor wax after the stickers were applied and the thing looks like it just rolled off the assembly line.  Not sure that any tank in combat would look that polished, but doing that after my sticker application will give you an enviable tank.

Here are some more pictures that buyer took and sent me, and here are some variants of the HISS.  These come on clear and you do not need to take any special steps.