It is possihble to splice into the low pressure side of the lines
without any consequence, as long as you double clamp the splice.
The high pressure side is another story and I wouldn't advise splicing
it.
I know it has been done, and I have done this in the past myself.
The high pressure side splices have a tendancy to leak simply due to the
high pressure in that side of the AC system.
Now, here is another thought.
Be prepared to buy another condensor when you replace the high pressure
line to it.
I would almost bet that the fitting at the condensor is frozen solid,
and you will destroy it upon removal being that it's in a direct line of
the blast of whatever hits the Van first--right behind the grill.

RC