I'll kiss cut, then perf cut to square.
Weed each decal.... Line then up / premask then all at once, flip it over and hand cut the extra premask using the paper as a guideline.
If you want to get fancy you could cut out reg marks on the outer 1" of your vinyl.... Weed it away, premask, load it as a print and cut after its pre-masked and it'll cut it to shape.
We did that for one job where we had 12,000 double sided street blades to do on reflective.. worked good. Doesn't work so good on bubble free material since the premask doesn't stick too well though.